This page shows what was measured, who it was measured in, and what that does not settle.
What Fexofenadine does in the body
Hay fever and long-running hives
Histamine is the chemical your body releases during an allergic reaction, and it works by switching on a receptor in your nose, eyes and skin. Fexofenadine sits in that receptor and holds it shut. What makes it unusual is where it does not go: the molecule carries an electrical charge that stops it crossing into the brain, and brain scans of people who have taken it show essentially none of it reaching the brain receptors that cause drowsiness. Older antihistamines went everywhere; this one stays where the allergy is.
What happened in people
Significant total symptom score improvement against placebo in 570 and in 861 patients, flat across a fourfold dose range
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The recorded finding that sits closest to something a person would notice. Written into the record, not signed off, and it carries no population or interval.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
The limit that matters most
Approved 1996 under NDA 020625 as a prescription capsule, now discontinued in that form with an explicit Federal Register finding that the withdrawal was not for safety or effectiveness reasons
Where it acts
Nasal and conjunctival mucosa and dermal postcapillary venules — peripheral H1 receptors only; measured brain H1 occupancy is essentially zero
Kind of result
Symptoms and quality of life
Supervision
RNAWiki has not recorded a supervision or regulatory status for this substance.
What the registries record it as
The substance registry classes this as chemical.
FDA substance registry · 2S068B75ZU · read 2026-08-29
Where each sentence above came from
No recorded sentence describes the change this makes in a way that stands on its own. The page opens with what it is taken for instead, and the recorded explanation follows below.
Shown as the opening line on this page.
A limit recorded against this substance. Not signed off as a reviewed claim.
The four opening statements run to 115 words.
Words this page uses
Four words worth knowing first
Chosen from what this page shows, with each one explained before the word it depends on.
Placebo
A placebo is a dummy treatment given so the real one can be compared with it.
A picture of it, and where the picture fails
A placebo is like a blank control in an experiment.
Where that stops being true. A blank does nothing. People given a placebo often do get better.
What people get wrong. A placebo effect is read as imaginary. The improvement is measured and real.
An inactive intervention matched in appearance to the test intervention, used to control for non-specific effects.
Comparator
A comparator is whatever the treatment was measured against.
A picture of it, and where the picture fails
It is like the other runner in a race.
Where that stops being true. A race has one winner. A study can show both arms improved.
What people get wrong. Results are read without asking what the other group got. Beating nothing is not beating a treatment.
The control condition against which the experimental intervention is assessed.
Randomisation
Randomisation means chance decides who gets which treatment.
A picture of it, and where the picture fails
It is like a coin toss deciding the groups.
Where that stops being true. A coin toss is fair once. Fairness here comes from doing it for everyone.
What people get wrong. It is thought to make groups identical. It makes them similar on average, including on things nobody measured.
Allocation of participants to arms by a chance process, so that unmeasured factors are balanced in expectation.
What happened in people◇Read from sources, not yet reviewed
What happened in people
Each card is one study: the exact question it asked, who was in it, and whether it showed what it set out to show.
Patient-assessed 12-hour reflective total symptom score before the evening dose, in ragweed seasonal allergic rhinitis
Phase 3, randomised, double-blind, placebo-controlled, 14 days
Compared against
A dummy treatment
Kind of result
A number that stands in for health
What was found
P<=0.003 for each of 60, 120 and 240 mg twice daily against placebo; no additional efficacy at the higher strengths
Repeated elsewhere
Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Patients with minimal or very severe symptoms during the placebo baseline period were excluded, so the enrolled population is a middle band rather than the population that takes the drug.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Change from baseline in average instantaneous 8 AM total symptom score, defined as the sum of individual symptom scores excluding nasal congestion
✓ The study showed what it set out to show
Who was studied
Casale 1999 (Allergy Asthma Proc 20:193-198)
How many people
861
Study design
Phase 3, randomised, double-blind, placebo-controlled, 14 days
Compared against
A dummy treatment
Kind of result
A number that stands in for health
What was found
P<=0.05 for both 120 mg and 180 mg once daily on instantaneous TSS and P<=0.0012 on reflective TSS; no statistical difference between the two doses
Repeated elsewhere
Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Nasal congestion was excluded from the primary score by definition, and it is the symptom this class relieves least.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
P<=0.0115 for all of 20, 60, 120 and 240 mg twice daily against placebo; 60 mg and above indistinguishable from each other
Repeated elsewhere
Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. No limitation is recorded for this study.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Coherence significantly better after fexofenadine or alcohol than after diphenhydramine; lane keeping impaired after alcohol and diphenhydramine relative to fexofenadine
Repeated elsewhere
Replicated
What this does not prove. Meeting one endpoint in one population does not carry to other goals or other people.
The limits of this study, and where it came from
Main limit. Single-dose, 40 subjects, one hour of driving. The finding that self-reported drowsiness did not predict impairment applies to the comparator, not to this drug, but it is the result with the widest practical reach.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Azelastine spray alone P=0.007 and azelastine plus fexofenadine P=0.003 against placebo; the two azelastine arms did not differ, so fexofenadine added nothing
Repeated elsewhere
Unreplicated
What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.
The limits of this study, and where it came from
Main limit. The trial was designed to test azelastine, not fexofenadine. Read from the other direction it is the only randomised evidence on what happens when this drug is continued in someone it has already failed.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Not reported. The registry record carries no posted results section.
Repeated elsewhere
Unreplicated
What this does not prove. A study that did not show an effect does not show that no effect exists anywhere.
The limits of this study, and where it came from
Main limit. The largest registered head-to-head this sponsor ran on the molecule, and its outcome is not public.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
RNAWiki holds 6 written-up human studies for this substance, each with the question it asked.
How we know it
Each card names the study, the number of people and what the study set out to measure.
What this does not prove
These summaries were written by a person and have not been signed off as reviewed claims.
Why it matters
A study that failed is as informative as one that worked, and both are here.
What we still do not know
No reviewed claim exists, so no exact population, effect size or interval is published yet.
What it changes in the body◇Read from sources, not yet reviewed
The path through the body
From what a person takes to what changes. A solid line is a step measured in people. A dashed line is a step nobody has measured that way.
Start
Fexofenadine
What a person takes: Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine.
The measurement behind this step
Taken with water. Absorption depends on an intestinal uptake transporter rather than on passive diffusion, so fruit juice substantially reduces the amount that reaches the blood while water does not. Very little of the drug is metabolised; most is excreted unchanged.
Getting in
Absorbed by a transporter, not by simply soaking through
The molecule is too charged to drift across the gut wall on its own. It has to be carried in by a specific protein, and that is why a glass of juice can cut the dose that reaches you to a third.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Fexofenadine is a substrate for organic anion transporting polypeptides at the apical membrane of the enterocyte and for P-glycoprotein efflux at the same surface. Furanocoumarins and bioflavonoids in grapefruit, orange and apple juice inhibit OATP at 5% of normal juice strength; normal-strength juice reduces AUC, Cmax and urinary excretion to 30% to 40% of the water values without altering half-life or renal clearance.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Reaching the cell
It stops at the blood-brain barrier
Carrying a permanent positive and a permanent negative charge, the molecule cannot slip through the fatty membranes that guard the brain, and a pump at that barrier throws back what does arrive. Scans confirm almost none of it gets in.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
The zwitterionic carboxylate-plus-protonated-piperidine structure gives very low passive permeability, compounded by P-glycoprotein efflux at the blood-brain barrier. Measured directly by [11C]doxepin PET, brain H1 receptor occupancy 90 minutes after fexofenadine 120 mg was -0.1%, against 26.0% for cetirizine 20 mg in the same study.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
What it acts on
It occupies the histamine receptor in the nose, eyes and skin
Where the allergy actually is, it parks in the receptor histamine needs and holds it inactive, so the histamine released by mast cells has nowhere to land.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Selective inverse agonism at peripheral HRH1 stabilises the inactive receptor conformation and suppresses both histamine-driven and constitutive Gq/11 signalling. Because the drug is not metabolised to any meaningful extent — it is largely excreted unchanged in faeces and urine — its activity does not depend on hepatic enzymes and it does not compete for them.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
The change it makes
What it deliberately does not touch: the heart
Its parent drug blocked a potassium channel that heart muscle needs to reset between beats, and people died of it. This molecule leaves that channel alone, and that is the entire reason it exists as a separate product.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
In isolated feline myocytes terfenadine blocked the delayed rectifier potassium current with a potency equal to quinidine; terfenadine carboxylate produced no inhibition at thirty times the terfenadine half-maximal concentration. In a paediatric safety programme of 875 children there was no statistically significant mean change from baseline in any electrocardiogram parameter, including QTc.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
What that does for a person
Symptoms fall, congestion much less so
Sneezing, itching, running nose and itchy eyes improve. A blocked nose improves least, which is why the primary score in the registration trials left it out.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
Nasal obstruction is driven substantially by cysteinyl leukotrienes and by late-phase eosinophilic infiltration rather than by histamine at H1, so H1 blockade addresses it poorly. Both registration studies showed a flat dose-response above the lowest tested strength — 60, 120 and 240 mg twice daily were indistinguishable — so there is no route to a larger effect by increasing exposure.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
What that does for a person
The trade it makes
By staying out of the brain it gives up whatever extra symptom relief the older drugs bought with sedation. It is the antihistamine to take before driving, and generally not the strongest one available.
╌╌Described, with no measurement named. No measurement is named for this step, so it is drawn as an unconfirmed link.
The measurement behind this step
The same physicochemical property that produces near-zero brain H1 occupancy limits tissue distribution generally. In a driving simulator crossover it was indistinguishable from placebo on coherence and lane keeping while diphenhydramine was worse than a 0.1% blood alcohol concentration, and self-reported drowsiness failed to predict actual impairment.
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
No suggested links are held for this record, so nothing is hidden from this path.
What we know
The record describes 6 steps from taking it to an effect in a person.
How we know it
Each step names the study behind it in the technical detail beside it.
What this does not prove
A change inside the body is a reason to look. It is not a result in a person.
Why it matters
A reader can see exactly where the chain stops being measured in people.
What we still do not know
No reviewed claim binds any of these steps to a named population.
What is missing or unclear◇Read from sources, not yet reviewed
Were people like you studied?
RNAWiki cannot tell whether a study fits you. It can show who was in it, and where the result stops carrying.
Who was studied
People similar to this profile were included.
Adults and children from two years of age, sold without a prescription in the United States. It is the usual choice when a person has to drive, fly or operate machinery.
Who is missing from the studies
Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
Where the result stopped carrying
The parent drug terfenadine was withdrawn effective 4 November 1998 on a finding that it was not shown to be safe for seasonal allergic rhinitis, after 25 reported cases of torsades de pointes
In 334 patients who had already failed a week of fexofenadine, adding it to azelastine nasal spray produced no benefit over the spray alone
Fruit juice, which nothing on the packet warns about at the point of swallowing, cuts absorption to roughly a third
Nasal congestion, the symptom patients rate most burdensome, was left out of the primary endpoint of both registration trials
This is a scope explorer, not a diagnosis engine.
It shows who was studied so you can see whether people similar to you were included.
RNAWiki cannot tell whether a study fits you. It can show who was in it.
What it would be like to take◇Read from sources, not yet reviewed
Why it might seem to do nothing
A real effect and a noticed effect are different things. These are the recorded reasons the two come apart.
It was studied in different people
The people in the studies were not much like the reader.
On this record: Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
The evidence may simply be wrong
Small early studies often do not hold up.
On this record: RNAWiki has not yet published a reviewed conclusion for this use.
Other reasons RNAWiki checked and found nothing for (11)
It was studied for a different goal
The studies measured something else entirely. Nothing in this record points to this reason.
A different form was studied
The studied form is not the form on the shelf. Nothing in this record points to this reason.
There was nothing to correct
Where a level is already normal, topping it up may change nothing. Nothing in this record points to this reason.
Something else had to happen too
In the studies it was paired with training, a diet or another treatment. Nothing in this record points to this reason.
The change is too small to feel
A real change can still sit below what a person notices. Nothing in this record points to this reason.
Day-to-day swing hides it
Sleep, food, stress and time of day move most numbers more than this would. Nothing in this record points to this reason.
Not enough time yet
The studies ran longer than the person has waited. Nothing in this record points to this reason.
It was not taken as studied
Missed days change the result, and studies count them. Nothing in this record points to this reason.
Something else changed at the same time
Two changes at once cannot be told apart afterwards. Nothing in this record points to this reason.
The product may not be what it says
Contents of a sold product are not always what the label states. Nothing in this record points to this reason.
No recorded reason
RNAWiki has nothing stored that would explain it. Nothing in this record points to this reason.
None of these is a reason to take more. Taking more is not a step this page ever suggests.
What it would be like to take◇Read from sources, not yet reviewed
What taking it involves
The recorded facts about getting hold of it and using it. Nothing here is a suggestion about what you should do.
How it is supplied
Prescription only
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
Read from the recorded approval status.
No source is stored against this line.
Form and route
Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form and route recorded on this substance.
No source is stored against this line.
Who oversees it
RNAWiki has not recorded a supervision or regulatory status for this substance.
❝ Quoted from a source
Where this came from
Copied from a source RNAWiki stored, with the source named.
No register row and no identity class settled the question.
No source is stored against this line.
What is in the pack
Taken with water. Absorption depends on an intestinal uptake transporter rather than on passive diffusion, so fruit juice substantially reduces the amount that reaches the blood while water does not. Very little of the drug is metabolised; most is excreted unchanged.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on how this is sold and what that means for what is in the pack.
No source is stored against this line.
Where it is registered
Regulatory records are listed in the technical disclosure at the foot of this page.
# Counted from records
Where this came from
A count of rows RNAWiki holds. It describes our records, not your body.
Register entries are stored per jurisdiction and shown with their dates.
No source is stored against this line.
Why people stop
Not recorded.
∅ Nothing recorded
Where this came from
RNAWiki holds nothing here and says so rather than guessing.
No record of why people stopped taking it is stored for this substance.
No source is stored against this line.
What it would be like to take◇Read from sources, not yet reviewed
What can go wrong
Sorted by where each line came from. A regulator's label and a report somebody sent in are not the same kind of fact.
·Worth asking a clinician aboutWritten into the record from the studies named on this page
The defining safety fact is a negative one: no cardiac potassium channel block, and no statistically significant change in any electrocardiogram parameter across a paediatric programme of 875 children. Adverse event incidence in the registration trials was indistinguishable from placebo — 30.2% against 30.0% in the once-daily study — with headache the commonest event in both arms. Sedation is not a class-typical feature here; psychomotor testing and a driving simulator both failed to separate it from placebo. Cleared largely unchanged, so exposure rises in impaired kidney function. The clinically meaningful interaction is with fruit juice and with transporter inhibitors, not with hepatic enzymes.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
Where this came from
Woosley RL, Chen Y, Freiman JP, Gillis RA. Mechanism of the cardiotoxic actions of terfenadine. JAMA 1993;269:1532-1536 (8445816) · a recorded source, not a stored snapshot
Monahan BP et al. Torsades de pointes occurring in association with terfenadine use. JAMA 1990;264:2788-2790 (1977935) · a recorded source, not a stored snapshot
FDA. Hoechst Marion Roussel, Inc., and Baker Norton Pharmaceuticals, Inc.; Terfenadine; Withdrawal of Approval of Two New Drug Applications and One Abbreviat… · a recorded source, not a stored snapshot
Over a long time. No completed tested study window is recorded, so long-term effects are not established by the registry record.
Groups the studies covered thinly. Which groups were under-represented in the studies has not been recorded for this substance. Pregnancy, breastfeeding, children, older adults, and people with liver or kidney conditions are commonly excluded from trials; nothing here says whether they were.
What is missing or unclear◇Read from sources, not yet reviewed
Does the exact form matter?
Evidence belongs to the exact thing that was tested. A different salt, a different mixture or a different preparation is a different question.
The form that was studied
Oral tablet (30, 60 and 180 mg), orally disintegrating tablet, oral suspension, and extended-release tablets combined with pseudoephedrine
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
The form used in the studies cited on this page.
No source is stored against this line.
What is sold
Absorption depends on an intestinal uptake transporter rather than on passive diffusion, so fruit juice substantially reduces the amount that reaches the blood while water does not. Very little of the drug is metabolised; most is excreted unchanged.
✎ Source-linked record
Where this came from
A person wrote this into the record with the study named beside it. No reviewer has signed it off.
Recorded notes on which forms are sold and how they compare.
No source is stored against this line.
What is recorded as being sold
292 products list this as an active ingredient in the United States drug directory. 245 of them contain it and nothing else.
FDA National Drug Code directory · 72559-027 · read 2026-08-29
They are sold as capsule, capsule, coated, powder, suspension, tablet and tablet, coated, taken oral.
FDA National Drug Code directory · 72559-027 · read 2026-08-29
The regulator's established pharmacologic class for it is histamine h1 receptor antagonists [moa] and histamine-1 receptor antagonist [epc].
FDA National Drug Code directory · 72559-027 · read 2026-08-29
233 published labels name it as an active ingredient. 192 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 667c87c2-c594-49e5-92a7-f8aa140642d6 · read 2026-08-29
Those labels are classed as human otc drug.
US prescribing information · 667c87c2-c594-49e5-92a7-f8aa140642d6 · read 2026-08-29
ALLEGRA ALLERGY is oral at HOW SUPPLIED Product: 50090-1234 NDC: 50090-1234-0 30 TABLET, FILM COATED in a BOTTLE, PLASTIC / 1 in a CARTON Product: 50090-1235 Product: 50090-1845, recorded as fda label in effect 2024-07-30 in the United States.
US prescribing information · b5ce28f8-f6c3-4113-9317-e1c98e5030ef · read 2026-08-30
Recorded price in US: 0.15683–0.24066 USD per one unit as the pricing file counts it — a tablet, capsule, patch or single item, across 21 priced products whose strengths and pack forms differ, as of 2026-08-26, paid by retail pharmacies buying the product, as surveyed by the Centers for Medicare & Medicaid Services. It is not a list price, an insurance price, or what anyone pays at a counter..
Recorded source · 2026-08-26 · read 2026-08-28
Evidence carries across two names for one substance. It does not carry across a salt, a mirror form or a mixture.
What it would be like to take◇Read from sources, not yet reviewed
What you could measure
This one is decided with a clinician, so this section holds questions to ask rather than a plan to run.
RNAWiki could not confidently classify this substance, so no self-experiment plan is offered.
Questions worth asking
Which of the trials of Fexofenadine studied people like me?
What was measured, and for how long?
Was the result a laboratory value or a health outcome?
What would we watch for, and when would we stop?
Tracking can show whether something changed for you. It cannot show what caused it.
RNAWiki records evidence. It does not say whether this substance is right for you.
What is missing or unclear◇Read from sources, not yet reviewed
Claims that go past the evidence
Things said about this substance that sound reasonable, and the exact step that is missing between the evidence and the claim.
✗Goes past the evidence
That a total symptom score improvement describes the full experience of allergic rhinitis, when nasal congestion was excluded from the primary score by design
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That there is a stronger dose for a patient who is not getting enough relief — 60, 120 and 240 mg twice daily were statistically indistinguishable
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That the public trial set characterises comparative performance, when the sponsor’s own 1,010-subject head-to-head against montelukast has no posted results
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
✗Goes past the evidence
That being the safe metabolite of a withdrawn drug says anything about efficacy — it says something about cardiac safety and nothing else
Why it sounds right. It follows from something real on this page: a body step, an animal result or a related finding.
The missing step. Nobody measured this in people for this use, or the study that did measure it did not show it.
What would change this
A study in people, for this exact use, measuring this exact thing, that a reviewer signs off.
RNAWiki has not yet published a reviewed conclusion for this use.
What is missing or unclear◇Read from sources, not yet reviewed
What nobody knows yet
Open questions, each with why it is open and what would close it.
Missing populations
Which groups were under-represented in the studies has not been recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing long-term data
No completed tested study window is recorded.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
No reviewed conclusion
RNAWiki has not yet published a reviewed conclusion for this use.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Missing interaction studies
No interaction was found in the registers checked. Not finding one is not the same as showing there is none.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Formulation uncertainty
Several salts, forms or products of Fexofenadine are recorded. Results from one form may not transfer to another.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
Mechanism not reviewed
No reviewed mechanism story exists for this substance.
Why it matters. Recorded by the evidence model as a gap on this record.
What would answer it
A study that measures it, and a reviewer to sign it off.
Last checked 2026-09-04. Searched: The sources listed in the receipts at the foot of this page.
What happened in people◇Read from sources, not yet reviewed
Check any of this yourself
Every line above traced back to the study it came from. This is the technical layer, and the vocabulary changes here.
Every line above can be traced to the study named beside it. Follow the link and read it.
The parent drug was withdrawn as unsafe, and the metabolite turned out to carry all the benefit and none of the risk
In plain words
Terfenadine was the first antihistamine that did not make people sleepy, and it was a bestseller. It also blocked a channel in heart muscle. When anything slowed its breakdown — an antibiotic, an antifungal, even grapefruit — the drug built up and the heart could go into a fatal rhythm. Investigation showed that the piece the liver normally chopped it into was the piece that treated the allergy. That piece is fexofenadine.
What was measured
Delayed rectifier potassium current block, terfenadine against terfenadine carboxylate, in isolated feline myocytes
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The first non-overdose case of torsades de pointes on prescribed terfenadine was reported in 1990 in a patient also taking ketoconazole, with measured serum showing excess parent drug and proportionately reduced metabolite. By April 1992, 25 cases had reached the FDA Spontaneous Reporting System. Woosley and colleagues showed in isolated feline myocytes that terfenadine was equipotent with quinidine as a blocker of the delayed rectifier potassium current, while terfenadine carboxylate did not inhibit it at thirty times the terfenadine half-maximal concentration — locating the toxicity in the parent and the therapy in the metabolite. FDA proposed withdrawal on 14 January 1997 (62 FR 1889) and withdrew NDA 18-949 (Seldane), NDA 19-664 (Seldane-D) and ANDA 74-475 effective 4 November 1998, on a finding that terfenadine is not shown to be safe for use in the treatment of seasonal allergic rhinitis. The hERG patch-clamp screen now run on essentially every new drug candidate exists largely because of this sequence.
Source
Woosley RL et al., JAMA 1993;269:1532-1536 (PMID 8445816); Monahan BP et al., JAMA 1990;264:2788-2790 (PMID 1977935); 63 FR 53444, 5 October 1998
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
verified
Review state
Written into the record, not signed off as a reviewed claim
Brain receptor occupancy of -0.1%, measured directly by PET
In plain words
Most claims that an antihistamine is non-drowsy rest on people ticking a box in a diary. For this drug someone put volunteers in a brain scanner and measured how much of the drug reached the receptors that cause drowsiness. The answer was, within measurement error, none.
What was measured
Brain histamine H1 receptor occupancy by [11C]doxepin PET, fexofenadine 120 mg against cetirizine 20 mg
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
In a double-blind, placebo-controlled crossover in 20 healthy Japanese volunteers, with [11C]doxepin PET performed in 12 of them plus 11 additional controls, brain histamine H1 receptor occupancy 90 minutes after dosing was -0.1% for fexofenadine 120 mg against 26.0% for cetirizine 20 mg. Hydroxyzine 30 mg was the positive control. On psychomotor testing — simple and choice reaction time, visual discrimination at four exposure durations — fexofenadine was not significantly different from placebo, was significantly less impairing than cetirizine on some tasks, and was significantly less impairing than hydroxyzine on all of them. Subjective sleepiness on fexofenadine was likewise indistinguishable from placebo.
Written into the record, not signed off as a reviewed claim
In a driving simulator it behaved like placebo while diphenhydramine behaved worse than alcohol
In plain words
Forty licensed drivers with hay fever drove an hour in a simulator after this drug, after an old antihistamine, after enough alcohol to be over the limit, and after a dummy. The old antihistamine was the worst of the four. This one was not distinguishable from the dummy.
What was measured
Coherence, lane keeping and response time in an hour of simulated driving, four-way crossover
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
A randomised, double-blind, double-dummy, four-treatment, four-period crossover in the Iowa Driving Simulator gave 40 licensed drivers aged 25 to 44 with seasonal allergic rhinitis a single dose of fexofenadine 60 mg, diphenhydramine 50 mg, alcohol to approximately 0.1% blood alcohol concentration, or placebo, at weekly intervals. The primary endpoint was coherence, the ability to match the varying speed of a lead vehicle. Coherence was significantly better after alcohol or fexofenadine than after diphenhydramine. Lane keeping — steering instability and centre-line crossings — was impaired after alcohol and after diphenhydramine relative to fexofenadine. Self-reported drowsiness did not predict lack of coherence, which is the finding with the most practical weight: people cannot tell how impaired they are.
Written into the record, not signed off as a reviewed claim
The pivotal trials measured a symptom score that left out the blocked nose
In plain words
The registration trials summed sneezing, itching, running and itchy eyes into one number and left nasal congestion out of that number. Congestion is the symptom people most want fixed and the one this class of drug helps least. Excluding it makes the drug look better than the experience of taking it.
What was measured
That a total symptom score improvement describes relief of allergic rhinitis as patients experience it, when nasal congestion was excluded from the score by design and the dose-response above the lowest tested strength is flat
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
In the once-daily registration study of 861 intent-to-treat patients with autumn seasonal allergic rhinitis, the primary efficacy measure is defined in the paper as change from baseline in average instantaneous 8 AM total symptom score, "the sum of individual symptom scores excluding nasal congestion." Both 120 mg and 180 mg beat placebo on that measure (p<=0.05) and on reflective assessments (p<=0.0012), with no statistical difference between the two doses. The earlier twice-daily study in 570 completers likewise found significant improvement at 60, 120 and 240 mg twice daily (p<=0.003) with no additional benefit at the higher strengths — a flat dose-response across a fourfold range, which is what a receptor already saturated at the lowest tested dose looks like, and which leaves no headroom for a patient who is not getting enough relief.
Written into the record, not signed off as a reviewed claim
Fruit juice cuts the absorbed dose to about a third
In plain words
Taking this tablet with orange, apple or grapefruit juice delivers roughly a third of the drug into the blood compared with taking it with water. Nothing about the experience tells you it has happened.
What was measured
Fexofenadine AUC, Cmax and urinary excretion with fruit juice against water, five-way crossover
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
In a randomised five-way crossover in 10 healthy subjects, grapefruit, orange and apple juices at normal strength each reduced fexofenadine area under the concentration-time curve, peak concentration and urinary excretion to 30% to 40% of the values obtained with water, with no change in time to peak, elimination half-life, renal clearance or urine volume — the signature of reduced absorption rather than altered clearance. The same juices at 5% of normal strength markedly reduced human OATP activity in vitro, while grapefruit juice and apple juice at that strength did not alter P-glycoprotein. The magnitude of the effect varied between individuals and was inversely related to how much drug each person absorbed with water.
Written into the record, not signed off as a reviewed claim
In people it had already failed, adding it back to a nasal spray contributed nothing
In plain words
A trial recruited people who had taken this drug for a week and barely improved. It compared a nasal spray alone against the spray plus this drug. The spray alone did just as well. For that group, the tablet was adding nothing.
What was measured
Change in total nasal symptom score at day 14, azelastine against azelastine plus fexofenadine
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
A multicentre, randomised, double-blind, placebo-controlled two-week study began with an open-label week of fexofenadine 60 mg twice daily. The 334 patients who improved by less than 25% to 33% were randomised to azelastine nasal spray, azelastine nasal spray plus fexofenadine, or double placebo. Both azelastine arms improved total nasal symptom score against placebo at day 14 (p=0.007 for spray alone, p=0.003 for the combination). Azelastine monotherapy was as effective as azelastine plus fexofenadine on the total nasal symptom score and on each of its four component symptoms, so the tablet added no measurable benefit on top of the spray in a population selected for having already failed it.
Written into the record, not signed off as a reviewed claim
It works in chronic hives, and above the lowest effective strength it stops improving
In plain words
In long-running hives, all four strengths tested beat the dummy tablet for itching and number of welts. Quadrupling the strength beyond the second-lowest did not help further.
What was measured
Mean daily change from baseline in pruritus severity and wheal count over four weeks against placebo
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
A four-week, double-blind, randomised, placebo-controlled dose-finding study in 418 patients with chronic idiopathic urticaria and moderate to severe pruritus compared fexofenadine 20, 60, 120 and 240 mg twice daily against placebo. All four doses were statistically superior to placebo for reducing pruritus severity and number of wheals over four weeks (p<=0.0115), and patients on fexofenadine reported significantly less interference with sleep and daily activities (p<=0.0014). Reductions were greater at 60 mg than at 20 mg and similar across 60, 120 and 240 mg. Adverse event incidence was similar across all groups with no dose-related increase.
Written into the record, not signed off as a reviewed claim
A 1,010-subject head-to-head against montelukast has no public result
In plain words
The manufacturer ran a single-centre trial in over a thousand people comparing this drug against a different kind of allergy medicine in a pollen exposure chamber. The registry entry has been there since 2008 and carries no results.
What was measured
That the published trial set describes this drug’s comparative performance, when the largest registered head-to-head comparison the sponsor ran has never reported
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
NCT00637611 is a single-centre, double-blind, randomised, parallel Phase 4 study sponsored by Sanofi comparing onset of action, efficacy and safety of a single dose of fexofenadine hydrochloride 180 mg against montelukast sodium 10 mg and placebo in seasonal allergic rhinitis subjects in an allergen exposure chamber, with an actual enrolment of 1,010. The registry record carries no posted results section. A trial of that size in a controlled challenge chamber is among the most informative designs available in this field, and its outcome is not in the public record.
Source
NCT00637611 registry record, Sanofi — actual enrolment 1,010, no results posted
Role in the trial
Not matched to a registered study
Identity check
no open identity hold
Audit mark
contested
Review state
Written into the record, not signed off as a reviewed claim
Where else this substance is registered
FDA substance identifier (UNII)
2S068B75ZU
RxNorm concept
997501
Checks this page had to pass
✓ Passed
Identity resolved
no open identity hold
✓ Passed
No unresolved merge across substance families
no quarantine open
✓ Passed
Every public sentence names a source
The opening statement carries the origin: Written into the record, not signed off.
✗ Not passed
Trial roles classified for highlighted evidence
No registered study is classified as testing this substance.
✓ Passed
No internal keys in reader text
enforced by the copy-contract test over the rendered page
✗ Not passed
Safety mode resolved
No register row and no identity class settled the question.
✓ Passed
Canonical metadata present
slug and display name present
What is missing or unclear◇Read from sources, not yet reviewed
How this medicine reached us
Kept near the foot of the page. A historical event moves up only when it changes something about this substance today.
What the approval register records
41 approved applications cover products containing this substance. The earliest was NDA020625, approved 19960725 to CHATTEM SANOFI.
This order is fixed in code and does not count clicks or time on the page.
What is not here
7 questions this page could not answer
These sections were prepared and left out because there was nothing to put in them. They are listed rather than hidden, so the gaps in this record are visible.
What was measured, goal by goal — found nothing in the sources checked.
How close this is to real life — found nothing in the sources checked.
Felt, measured, or meaningful — found nothing in the sources checked.
How long anything takes — found nothing in the sources checked.
What it may clash with — found nothing in the sources checked.
Other ways to the same goal — found nothing in the sources checked.
What changed on this page — found nothing in the sources checked.
The record as stored
The full record, for auditing
Everything above is built from what is below. This layer keeps the technical vocabulary, record identifiers and every stored row, so a reader who wants to check the page can.
The older medicine-wide conclusion held in this record
Written for a clinical reader, and about the medicine as a whole rather than about one indication, population and set of trials. RNAWiki does not treat it as a programme conclusion and no reviewer has signed it off in that form. It is here word for word because it is what the record holds.
The carboxylic-acid metabolite of terfenadine — it blocks the histamine H1 receptor while, unlike its parent, leaving the cardiac delayed-rectifier potassium current untouched even at thirty times the concentration at which terfenadine half-blocks it, and positron emission tomography measures its brain H1 receptor occupancy at -0.1% against 26.0% for cetirizine; it beat placebo on total symptom score in 570 and 861 patients, and in both of those trials the primary score excluded nasal congestion.
Recorded evidence blocks (7)
Q1
On the Fexofenadine label: indicated for what?
"Uses temporarily relieves these symptoms due to hay fever or other upper respiratory allergies: runny nose sneezing itchy, watery eyes itching of the nose or throat": indications and usage on Fexofenadine's label. DailyMed label · 0a3d4d1f-a99f-4d0a-bb28-b2409a9e073a · 2026-08-25
Q2
67 registered trials of Fexofenadine — at which phases?
Registered studies posting no result
54 of 67
67 registered studies of Fexofenadine: 23 phase4, 21 phase1, 11 phase2, 8 phase3, 4 na, 1 early phase1, 1 na or unstated. CLINICALTRIALS_SNAPSHOT · 2026-09-01
243 with a PubMed record
Show the evidence
phase4
23
phase1
21
phase2
11
phase3
8
na
4
early phase1
1
8 more recorded rows
na or unstated
1
completed
51
recruiting
6
unknown
4
terminated
3
active not recruiting
1
not yet recruiting
1
withdrawn
1
recorded 2026-09-01 · last checked 2026-09-04
Q3
3 of Fexofenadine's trials stopped: futility/efficacy, other?
"Original PI left institution."; 3 of 67 registered studies
Show the evidence
Trial
NCT00927329
withdrawn; "Original PI left institution."
NCT03425097
terminated; "The study was terminated due to insufficient evidence for Fexofenadine efficacy to treat GERD symptoms after the interim analysis."
NCT03933007
terminated; "faillure of recrutement"
recorded 2026-09-01 · last checked 2026-09-04
Q4
Human studies of Fexofenadine used Fexofenadine Tablets 180 mg — over how long?
Human studies of Fexofenadine used "Fexofenadine Tablets 180 mg". ClinicalTrials.gov · 2026-09-01
11 recorded entries; human; tablet; also "Allegra® Tablets 180 mg", "Fexofenadine 180 mg tablets", "ALLEGRA® 180 mg tablets"
Show the evidence
human
NCT00647985
Fexofenadine Tablets 180 mg
NCT00647985
Allegra® Tablets 180 mg
NCT00835276
Fexofenadine 180 mg tablets
NCT00835276
ALLEGRA® 180 mg tablets
NCT01066754
Allegra 180 mg Tablets
NCT01586091
Fexofenadine 60 Mg Oral Tablet
5 more recorded rows
humanNCT01731067
fexofenadine 25mg
humanNCT02056743
Fexofenadine 30mg
humanNCT02438072
Fexofenadine (25mg, R06AX26 )
humanNCT04726345
Fexofenadine Hcl 180Mg Tab
humanNCT05150899
tablet; fexofenadine 180 mg Oral tablet
recorded 2026-09-01 · last checked 2026-09-04
Q5
Which 31 trials of Fexofenadine posted no result?
Posted no result
31 of 31 completed trials
Registrations
NCT01066754, NCT01066767, NCT00637611, NCT00638118, NCT00794248 and NCT00783133, and 25 more
Completion dates
oldest 2002-05; newest 2023-09-13
Show the evidence
Trial
NCT01066754
2002-05
NCT01066767
2002-05
NCT00637611
2003-04
NCT00638118
2003-05
NCT00794248
2003-05
NCT00783133
2003-06-01
14 further recorded trials
NCT00637585
2003-07
NCT00794768
2003-07
NCT00044811
2003-10
NCT00044824
2003-10
NCT00647985
2003-11
NCT00649376
2003-11
NCT00636870
2004-01
NCT00637884
2004-02
NCT00783146
2004-10-01
NCT00783211
2004-10-01
NCT00637455
2005-01
NCT00261079
2006-10
NCT00420082
2006-12
NCT01033396
2010-05
Q6
At the median, Fexofenadine's trials enrolled 64 people — anything larger?
Median enrolment
64
Largest enrolment
2804
Registered trials counted
67
Q7
What do 371 spontaneous reports say about Fexofenadine — and not say?
These are reports people sent to a regulator. They do not show the medicine caused the reaction. Nobody counted how many people took the medicine and reported nothing. The same event can be reported more than once, and many reports are incomplete. News coverage, lawsuits and new warnings change how often people report. A count is not a rate and not a risk.
Fexofenadine appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 371 reaction mentions were counted: drug hypersensitivity 81; urticaria 50; somnolence 44; hepatic function abnormal 37. FAERS via Open Targets · CHEMBL1200618 · 2026-06-24
Show the evidence
drug hypersensitivity
81
urticaria
50
somnolence
44
hepatic function abnormal
37
palpitations
32
liver disorder
31
4 more recorded rows
alanine aminotransferase increased
28
angioedema
28
electrocardiogram qt prolonged
22
urinary retention
18
recorded 2026-06-24 · last checked 2026-09-04
Where it is registeredIdentifiers, relations and other names
ChEMBL 37 — CC BY-SA 3.0 Unported · ClinicalTrials.gov — US Government work · Open Targets 26.06 — CC0 · mixed register set; per-register licences in docs/specs/corpus-20k-sources.md · openFDA / DailyMed — US Government work
✗ required summary fields resolved: 4 required field(s) not terminal: Why people use it, Best-supported result, Biggest unanswered question, Human evidence
✓ public claims reviewed: 0 reviewed claim(s); drafts are never rendered
✓ source coverage passed: 6 source rows
✓ no critical contamination: no quarantine open
✓ canonical metadata passed: slug and display name present
✓ no raw internal fields: enforced by the copy-contract test over the rendered page
This is a record of evidence. It is not medical advice, and it does not say this substance suits you. Nothing here says any substance on RNAWiki is appropriate for a child.