This page shows what was measured, who it was measured in, and what that does not settle.
What Bimatoprost does in the body
Used to lower eye pressure and, in another product, grow eyelashes.
Fluid drains out of the eye through two routes, and one of them runs through the ring of muscle behind the iris. Bimatoprost switches on a receptor there, and the cells respond by dismantling some of the connective tissue packed between the muscle fibres. The spaces widen, fluid leaves faster, and pressure falls. The same receptor sits in hair follicles and in the fat pads around the eye, which is why lashes grow and the eye socket can hollow.
What happened in people
Across 114 studies, bimatoprost lowered eye pressure more than any other single drop.
✓ Reviewed first-read answer
Where this came from
A person wrote this and a reviewer approved it against this exact record. It carries no effect size.
A reviewer approved this against this record. The reviewed-claim record carrying the exact population and effect size does not exist yet.
No source is stored against this line.
The limit that matters most
Direct evidence that pressure lowering preserves vision comes from a different medicine.
Where it acts
Ciliary muscle and uveoscleral outflow pathway at the front of the eye; and, for the cosmetic product, the hair follicles at the upper eyelid margin
Kind of result
The kind of result is not recorded
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 · QXS94885MZ · read 2026-08-29
Its recorded molecular formula is C25H37NO4, weighing 415.58.
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
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.
The limit a reviewer approved as the one that matters most here.
The four opening statements run to 105 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.
Diurnal intraocular pressure at 8 AM, 10 AM and 4 PM over 12 months
✓ The study showed what it set out to show
Who was studied
Bimatoprost Study Groups 1 and 2, one-year (Higginbotham 2002)
How many people
1198
Study design
Two identical multicentre, randomised, double-masked, 12-month trials
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
At 10 AM month 12, -7.6 mmHg (30%) bimatoprost once daily against -5.3 mmHg (21%) timolol, P < .001; 58% against 37% at or below 17 mmHg, P < .001
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. Twice-daily bimatoprost performed worse than once-daily, an inverse dose-response the paper reports without explaining. Hyperemia was significantly more frequent on bimatoprost than timolol.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
At 8 AM month 3, -9.16 mmHg (35.2%) once daily, -7.78 mmHg (30.4%) twice daily, -6.74 mmHg (26.2%) timolol; P < 0.001 for once daily against timolol at all time points
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. Bimatoprost caused significantly more hyperemia and eyelash growth than timolol. The eyelash finding was later developed into a separate cosmetic product rather than treated only as a side effect.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Between-group differences under 0.9 mmHg throughout; 0.01% met equivalence criteria; moderate to severe hyperemia 3.2% against 9.1%, P = .019
Repeated elsewhere
Partially 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. Sponsored by the manufacturer to support a lower-concentration product. The result is that the concentration marketed for nine years was three times what was needed, which the trial reports without saying so.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
Two identical randomised phase 3 studies, 20-month follow-up
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
82% of implants absent or ≤25% of initial size by 52 weeks, 95% by month 20; reported descriptively
Repeated elsewhere
Partially 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. Biodegradation was variable between patients and implants frequently swelled between weeks 6 and 28 before shrinking. The paper states that studies are still in progress to determine appropriate timing for re-administration.
How far it carries. This study is recorded from the curated record, not from the registry match.
Form and route. Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
RNAWiki holds 4 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
Bimatoprost
What a person takes: Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant.
The measurement behind this step
An aqueous solution instilled once daily. Twice-daily dosing was tested in both pivotal programmes and lowered pressure less than once-daily, so the schedule is not a convenience choice. The intracameral implant places the same molecule inside the anterior chamber and biodegrades over roughly a year, with 82% of implants absent or at a quarter of their initial size by 52 weeks.
Getting in
One evening drop, and most of it drains away
A single drop at night. The eye holds a fraction of it and the rest goes down the tear duct. Trying to help by using it twice a day makes it work less well, which is unusual for a drug.
╌╌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
Bimatoprost 0.03% or 0.01% is instilled once daily in the evening. Two independent randomised trials found once-daily dosing superior to twice-daily on pressure and on tolerability, a departure from ordinary dose-response usually attributed to receptor desensitisation with more frequent exposure.
It crosses the cornea, and enzymes cut the amide slowly
The molecule carries a chemical group that is cut off inside the eye to release the active form. Unlike similar drugs it is an amide, which is cut far more slowly than an ester, so both forms are present at once.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
Bimatoprost is an ethylamide, hydrolysed by ocular amidases to 17-phenyl-trinor prostaglandin F2-alpha. In human aqueous humour after seven days of once-daily dosing, free acid reached 22.0 nmol/l at two hours against 5.7 nmol/l for the intact amide, and 7.0 against 1.1 nmol/l at twelve hours. Slow amide hydrolysis, rather than a distinct receptor, is the parsimonious explanation for the drug’s pharmacology.
The released active form binds the same receptor latanoprost and travoprost bind, on the muscle ring behind the iris.
╌╌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
17-phenyl-trinor prostaglandin F2-alpha is a potent agonist at the FP prostanoid receptor expressed on ciliary muscle and trabecular meshwork. The measured aqueous concentration is sufficient to account for the observed pressure reduction, which is the basis for treating bimatoprost as a slow prodrug rather than a distinct pharmacological class.
Connective tissue is remodelled and the drain widens
The receptor tells the cells to break down some of the packing between the muscle bundles. Channels open where there were none, over days to weeks rather than instantly.
╌╌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
FP receptor activation upregulates matrix metalloproteinases in the ciliary muscle, remodelling the extracellular matrix of the uveoscleral outflow pathway and reducing its hydraulic resistance. The response is transcriptional, which is why the full effect takes weeks to establish and why the pressure reduction is sustained rather than pulsatile.
Pressure falls further than with any other single drop
Pressure drops by around five and a half millimetres of mercury on average, more than any competitor. At the twelve-month mark in the big trial it was down 30% against timolol’s 21%.
──Measured in people. Written by a person from the study named beside the step. Not signed off as a reviewed claim.
The measurement behind this step
Pooled reduction is 5.61 mmHg (95% credible interval 4.94 to 6.29) at three months, first of fourteen agents. At month 12 at the 10 AM peak-timolol time point, reduction was 7.6 mmHg (30%) against timolol’s 5.3 mmHg (21%), P<.001, with 58% of bimatoprost patients at or below 17 mmHg against 37%.
The same receptor is in lashes, lids and orbital fat
Hair follicles have this receptor too, so lashes grow longer, thicker and darker — enough that the same drug is sold as a cosmetic. The fat pads around the eye have it as well, and there the effect is loss rather than growth.
╌╌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
FP activation in eyelash follicles lengthens the anagen growth phase, an effect large enough that the molecule is separately approved at a cosmetic concentration for eyelash hypotrichosis. FP activation in orbital preadipocytes inhibits adipogenesis, producing the deepened upper eyelid sulcus and orbital fat atrophy of prostaglandin-associated periorbitopathy. Both are on-target effects of the intended receptor in unintended tissue.
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 with open-angle glaucoma or ocular hypertension, as a once-daily evening drop. The eyelash product is a different concentration applied to the lid margin and is not a glaucoma treatment.
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.
What the label states about particular groups
On pediatric, the label states: “Use in pediatric patients below the age of 16 years is not recommended because of potential safety concerns related to increased pigmentation following long-term chronic use.”
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
On older people, the label states: “No overall clinical differences in safety or effectiveness have been observed between elderly and other adult patients.”
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
On people who are pregnant, the label states: “Risk Summary There are no adequate and well-controlled studies of bimatoprost ophthalmic solution, 0.03% administration in pregnant women.”
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
On people who are breastfeeding, the label states: “Risk Summary It is not known whether topical ocular treatment with bimatoprost ophthalmic solution, 0.03% could result in sufficient systemic absorption to produce detectable quantities in human milk.”
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
Where the result stopped carrying
Twice-daily dosing lowered pressure less than once-daily in both the three-month and the twelve-month trials, the opposite of a dose-response
Conjunctival hyperemia was the commonest adverse effect throughout and drove development of a formulation at one third the concentration nine years after launch
Prostaglandin-associated periorbitopathy was not identified in the registration programme and is worst with this agent in the class
The mechanism the drug was marketed on — a distinct prostamide receptor — lost its necessity to a mass spectrometry study of 31 human eyes
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
Given by a clinician
❝ 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
Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
✎ 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
An aqueous solution instilled once daily. Twice-daily dosing was tested in both pivotal programmes and lowered pressure less than once-daily, so the schedule is not a convenience choice.
✎ 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. The rest of the recorded wording: The intracameral implant places the same molecule inside the anterior chamber and biodegrades over roughly a year, with 82% of implants absent or at a quarter of their initial size by 52 weeks.
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
Conjunctival hyperemia, the commonest adverse effect and significantly more frequent than with timolol, reduced from 9.1% to 3.2% moderate-to-severe by the lower concentration. Eyelash lengthening, thickening and darkening, marked enough to support a separate cosmetic approval. Increased brown iris pigmentation, permanent. Eyelid skin darkening. Prostaglandin-associated periorbitopathy with deepening of the upper eyelid sulcus and orbital fat atrophy, described after approval, worst in this agent within the class, and partially reversible on switching. Rare macular oedema, chiefly in aphakic or pseudophakic eyes with a torn posterior capsule. No systemic beta-blockade and no respiratory or cardiac contraindications.
Nobody counted how many people took this and were fine, so this cannot be turned into a rate.
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
Topical ophthalmic solution 0.03% and 0.01%, once daily in the evening; also a biodegradable intracameral implant
✎ 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
Twice-daily dosing was tested in both pivotal programmes and lowered pressure less than once-daily, so the schedule is not a convenience choice.
✎ 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. The rest of the recorded wording: The intracameral implant places the same molecule inside the anterior chamber and biodegrades over roughly a year, with 82% of implants absent or at a quarter of their initial size by 52 weeks.
No source is stored against this line.
What is recorded as being sold
53 products list this as an active ingredient in the United States drug directory. 53 of them contain it and nothing else.
FDA National Drug Code directory · 57741-3000 · read 2026-08-29
They are sold as gel, implant, powder and solution/ drops, taken intracameral and ophthalmic.
FDA National Drug Code directory · 57741-3000 · read 2026-08-29
The regulator's established pharmacologic class for it is prostaglandin analog [epc] and prostaglandins [cs].
FDA National Drug Code directory · 57741-3000 · read 2026-08-29
20 published labels name it as an active ingredient. 20 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-29
Those labels are classed as human prescription drug.
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-29
Bimatoprost is ophthalmic at 3 DOSAGE FORMS AND STRENGTHS Ophthalmic solution containing bimatoprost 0.3 mg/mL., recorded as fda label in effect 2022-04-12 in the United States.
US prescribing information · 2a4b5b6b-fc47-40d2-8396-ff60511a4cd1 · read 2026-08-30
Recorded price in US: 4.23499–50.40188 USD per one millilitre, across 26 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 Bimatoprost 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 the strongest pressure lowering in the class produces the best preserved vision — no trial of this drug has used a visual outcome
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 bimatoprost acts intact at a distinct prostamide receptor, an argument human aqueous humour measurement made unnecessary
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 sub-millimetre advantage over latanoprost and travoprost is clinically meaningful; the pooling authors say it may not be
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 eyelash growth and periorbitopathy are separable phenomena — both follow from FP activation in tissue the drop was not aimed at
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 Bimatoprost 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.
First of fourteen first-line drops, and the margin is under a millimetre
In plain words
Pooling 114 trials, bimatoprost lowers pressure more than any other single drop: 5.61 millimetres of mercury. Latanoprost is at 4.85 and travoprost at 4.83. The authors say the differences within the class may not be clinically meaningful.
What was measured
Mean intraocular pressure reduction at 3 months, pooled across 114 randomised trials
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
In the Bayesian network meta-analysis of 114 randomised trials with data from 20,275 participants, mean reduction in intraocular pressure at 3 months was 5.61 mmHg (95% credible interval 4.94 to 6.29) for bimatoprost, the highest of fourteen first-line agents. Latanoprost followed at 4.85 (4.24 to 5.46) and travoprost at 4.83 (4.12 to 5.54), with credible intervals overlapping bimatoprost’s. Timolol was at 3.70 and the carbonic anhydrase inhibitors at roughly 2.4. The authors state that bimatoprost, latanoprost and travoprost are among the most efficacious drugs, that the within-class differences were small and may not be clinically meaningful, and that adverse effects, patient preferences and cost should all enter the choice.
Written into the record, not signed off as a reviewed claim
Beat timolol at every hour of every visit across a full year
In plain words
Two identical year-long trials put 1,198 patients on bimatoprost once daily, bimatoprost twice daily or timolol. Once-daily bimatoprost lowered pressure more than timolol at every measurement time at every visit, and got more patients to a low target.
What was measured
Diurnal intraocular pressure at 12 months, bimatoprost once and twice daily against timolol
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Two identical multicentre, randomised, double-masked, one-year trials enrolled 474 patients on bimatoprost 0.03% once daily, 483 on bimatoprost 0.03% twice daily and 241 on timolol 0.5% twice daily. Bimatoprost once daily gave significantly lower mean intraocular pressure than timolol at every time of day at each study visit (P<.001). At 10 AM, the peak timolol effect, at month 12, mean reduction from baseline was 7.6 mmHg (30%) with bimatoprost against 5.3 mmHg (21%) with timolol (P<.001). Pressure at or below 17 mmHg was reached by 58% of bimatoprost once-daily patients against 37% on timolol (P<.001). Twice-daily bimatoprost was significantly better than timolol at most time points but worse than the once-daily regimen. Hyperemia was the commonest adverse effect and significantly more frequent on bimatoprost once daily than timolol (P<.001).
Written into the record, not signed off as a reviewed claim
More often is worse: twice daily lowered pressure less than once daily
In plain words
In both the three-month and the twelve-month trials, taking bimatoprost twice a day worked less well than taking it once. That is the opposite of what a dose-response curve should look like.
What was measured
Intraocular pressure reduction, once-daily against twice-daily dosing of the same drug
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
In the three-month trial of 596 patients randomised 2:2:1, mean reduction from baseline at 8 AM at month 3 was 9.16 mmHg (35.2%) with bimatoprost 0.03% once daily, 7.78 mmHg (30.4%) twice daily and 6.74 mmHg (26.2%) with timolol twice daily. The one-year trials reproduced the pattern: once-daily dosing was superior to twice-daily at most time points, and the authors state directly that bimatoprost once daily provides pressure lowering superior to timolol or to bimatoprost twice daily. Once-daily dosing also produced better ocular tolerability. The usual explanation offered is receptor downregulation or desensitisation with more frequent exposure, and it remains an explanation rather than a measurement. What is not in doubt is the observation, in two independent trials totalling nearly 1,800 patients.
Written into the record, not signed off as a reviewed claim
Reddest eye in the class, and the maker cut the dose to fix it
In plain words
Conjunctival redness was the commonest side effect in every trial and clearly worse than with timolol. Allergan responded by developing a formulation at one third the concentration, and it lowered pressure just as well.
What was measured
Macroscopic conjunctival hyperemia and intraocular pressure across three concentrations over 12 months
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
A twelve-month randomised, double-masked trial compared bimatoprost 0.01% (n=186), 0.0125% (n=188) and 0.03% (n=187). Differences in mean intraocular pressure between the lower concentrations and 0.03% were under 0.9 mmHg throughout follow-up, and bimatoprost 0.01% met predetermined equivalence criteria against 0.03% — 95% confidence interval of the between-group difference within plus or minus 1.5 mmHg at all time points and within plus or minus 1 mmHg at most. Treatment-related adverse events were significantly reduced at both lower concentrations (P ≤ .034). Moderate to severe increase from baseline in macroscopic hyperemia occurred in 3.2% on 0.01%, 9.0% on 0.0125% and 9.1% on 0.03% (P = .019 for 0.01% against 0.03%). The finding that a third of the concentration is equally effective and a third as red is a retrospective judgement on the original dose selection.
Written into the record, not signed off as a reviewed claim
The orbit hollows, and the receptor being hit is the intended one
In plain words
Long-term users can develop a sunken look around the treated eye. Bimatoprost is the agent in the class where it is worst, and switching to latanoprost has been shown to reverse part of it.
What was measured
Upper eyelid sulcus depth on switching from bimatoprost to latanoprost, and FP-mediated inhibition of adipogenesis in vitro
Effect estimate
No reviewed effect estimate exists for this record.
Limits
This entry records a failure.
From the source
Prostaglandin-associated periorbitopathy — deepening of the upper eyelid sulcus, orbital fat atrophy, ptosis, periocular skin darkening — was described from clinical practice rather than from registration trials. A Japanese series specifically documented recovery from deepening of the upper eyelid sulcus after switching from bimatoprost to latanoprost, which establishes both that the effect is real and that it is dose- or agent-dependent within the class. Experimental work then showed that activation of the prostanoid FP receptor inhibits adipogenesis, giving a mechanism in which the orbital fat loss is an on-target consequence of the receptor the drug is prescribed to activate. Unilateral treatment produces visible facial asymmetry, which is how it is usually noticed, and no study provides a reliable incidence figure.
Written into the record, not signed off as a reviewed claim
The prostamide receptor argument met a mass spectrometer
In plain words
The manufacturer argued for years that bimatoprost works through a receptor of its own, distinct from the one latanoprost hits. Then someone measured what was actually inside treated human eyes, and found plenty of the ordinary active acid.
What was measured
That bimatoprost acts intact at a distinct prostamide receptor rather than as a slow prodrug of an FP agonist — a mechanism claim that human aqueous humour measurement made unnecessary rather than impossible
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
Bimatoprost is an ethylamide rather than an ester, and the manufacturer’s position was that it acts intact at a distinct prostamide-sensitive receptor rather than as a prodrug of an FP agonist. A prospective, masked, vehicle-controlled study treated one eye of each of 31 cataract patients with bimatoprost 0.03% or vehicle once daily for seven days before surgery and assayed aqueous humour by high-pressure liquid chromatography and mass spectrometry at paracentesis. Free acid concentrations were 22.0 nmol/l (SEM 7.0, n=12) at two hours and 7.0 nmol/l (4.6, n=8) at twelve hours, against 5.7 and 1.1 nmol/l for the intact amide, with both undetectable after vehicle. The authors concluded that sufficient free acid — a potent FP prostanoid receptor agonist — is present to account for the pressure reduction. That does not disprove a prostamide receptor. It removes the need to invoke one, and the burden of proof moved with it.
Written into the record, not signed off as a reviewed claim
The pressure result is real, the vision result is borrowed
In plain words
Every trial of this drug measures pressure. The evidence that lowering pressure preserves sight comes from trials of other drugs, and the strongest of those tested latanoprost, not this one.
What was measured
That the largest pressure reduction in the class produces the best preserved vision — never tested for this drug, and the drug that was tested against placebo for vision is the one that lowers pressure slightly less
Effect estimate
No reviewed effect estimate exists for this record.
Limits
See the technical detail.
From the source
The registration programme for bimatoprost, from the three-month trial in 596 patients through the one-year trials in 1,198, used intraocular pressure as the outcome throughout. No trial of bimatoprost has used visual field progression or optic disc deterioration as a primary endpoint. The placebo-controlled visual function evidence in this therapeutic area comes from UKGTS, which randomised 516 patients to latanoprost or identical placebo drops and found time to visual field deterioration delayed with an adjusted hazard ratio of 0.44 (95% CI 0.28 to 0.69). The Ocular Hypertension Treatment Study and the Early Manifest Glaucoma Trial support pressure lowering at class level, using any commercially available agent and betaxolol respectively. Bimatoprost’s claim to preserve vision is therefore an inference from its superior pressure lowering plus the class-level evidence, and the class-level evidence was not generated with this molecule.
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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.
A synthetic prostamide that reaches the FP prostanoid receptor mostly as its hydrolysed free acid and widens the eye’s secondary drainage route, producing the largest pressure reduction of any single first-line drop — 5.61 mmHg at three months across 114 pooled trials, and 7.6 mmHg (30%) against timolol’s 5.3 mmHg (21%) at one year in 1,198 patients — while causing the highest rate of red eye in its class and eyelash growth marked enough to be sold separately as a cosmetic.
Recorded evidence blocks (9)
Q1
On the Bimatoprost label: indicated for what?
"Bimatoprost ophthalmic solution 0.03% is indicated for the reduction of elevated intraocular pressure in patients with open angle glaucoma or ocular hypertension. Bimatoprost ophthalmic solution 0.03% is a prostaglandin analog indicated for the reduction of elevated intraocular pressure in patients with open angle…": indications and usage on Bimatoprost's label. DailyMed label · 19b21ff7-847c-3dc9-e063-6394a90a20cc · 2026-01-09
Q2
89 registered trials of Bimatoprost — at which phases?
Registered studies posting no result
36 of 89
89 registered studies of Bimatoprost: 31 phase4, 21 phase3, 19 phase2, 11 na or unstated, 5 na, 5 phase1, 2 early phase1. CLINICALTRIALS_SNAPSHOT · 2026-09-01
205 with a PubMed record
Show the evidence
phase4
31
phase3
21
phase2
19
na or unstated
11
na
5
phase1
5
8 more recorded rows
early phase1
2
completed
76
unknown
5
terminated
3
withdrawn
2
active not recruiting
1
no longer available
1
recruiting
1
recorded 2026-09-01 · last checked 2026-09-04
Q3
4 of Bimatoprost's trials stopped: funding/business, other?
Bimatoprost 0.03% Formulation B Ophthalmic Solution
recorded 2026-09-01 · last checked 2026-09-04
Q5
Bimatoprost's half-life is 45 minutes — which schedules were studied?
45 minutes, the half-life Bimatoprost's label states: "Excretion Following an intravenous dose of radiolabeled bimatoprost (3.12 mcg/kg) to six healthy subjects, the maximum blood concentration of unchanged drug was 12.2 ng/mL and decreased rapidly with an elimination half-life of approximately 45 minutes." DailyMed label · 19b21ff7-847c-3dc9-e063-6394a90a20cc · 2026-01-09
Show the evidence
half lifepharmacokinetics
45 minutes; Excretion Following an intravenous dose of radiolabeled bimatoprost (3.12 mcg/kg) to six healthy subjects, the maximum blood concentration of unchanged drug was 12.2 ng/mL and decreased rapidly with an elimination half-life of approximately 45 minutes.
metabolismpharmacokinetics
Elimination Metabolism Bimatoprost is the major circulating species in the blood once it reaches the systemic circulation following ocular dosing.
recorded 2026-01-09 · last checked 2026-09-04
Q6
Which 20 trials of Bimatoprost posted no result?
Posted no result
20 of 20 completed trials
Registrations
NCT00847483, NCT00651859, NCT01655758, NCT00652496, NCT00187577 and NCT00300443, and 14 more
Completion dates
oldest 2002-08; newest 2022-08-24
Show the evidence
Trial
NCT00847483
2002-08
NCT00651859
2004-01
NCT01655758
2004-02
NCT00652496
2005-05
NCT00187577
2006-03
NCT00300443
2007-06
14 further recorded trials
NCT01200251
2008-12
NCT01206361
2010-08
NCT00941096
2010-11
NCT01168414
2011-02
NCT01448837
2011-03
NCT01542710
2011-12
NCT01737853
2012-06
NCT01978015
2013-01
NCT02059655
2016-03
NCT02155049
2017-05
NCT02505776
2018-05-21
NCT02571712
2018-06-21
NCT04738149
2022-05-15
NCT04828057
2022-08-24
Q7
At the median, Bimatoprost's trials enrolled 106 people — anything larger?
Median enrolment
106
Largest enrolment
2580
Registered trials counted
87
Q8
What do 3542 spontaneous reports say about Bimatoprost — 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.
Bimatoprost appears in spontaneous reports to regulators. Across the 10 most-reported reaction terms, 3542 reaction mentions were counted: ocular hyperaemia 622; treatment failure 589; eye irritation 494; eye pruritus 369. FAERS via Open Targets · CHEMBL1200963 · 2026-06-24
Show the evidence
ocular hyperaemia
622
treatment failure
589
eye irritation
494
eye pruritus
369
madarosis
341
erythema of eyelid
322
4 more recorded rows
eye swelling
226
hypersensitivity
202
eyelid oedema
192
eyelids pruritus
185
recorded 2026-06-24 · last checked 2026-09-04
Q9
Which 10 reactions does Bimatoprost's label not list?
ChEMBL 37 — CC BY-SA 3.0 Unported · ChEMBL ATC CC BY-SA · 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
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✓ 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
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