This page shows what was measured, who it was measured in, and what that does not settle.
What Hydroquinone does in the body
The gradual bleaching of hyperpigmented skin conditions age and liver spots, freckles, and other unwanted areas of melanin hyperpigmentation
From the FDA-approved label: The mechanism of action of the active ingredients in TRI-LUMA Cream in the treatment of melasma is unknown.
What happened in people
RNAWiki has not yet published a reviewed conclusion for this use.
§ A fixed RNAWiki sentence
Where this came from
Wording RNAWiki always uses, not a finding about this substance.
No reviewed claim names a result for any goal on this record.
No source is stored against this line.
The limit that matters most
Not recorded.
Where it acts
Not recorded.
Kind of result
No result is published, so no kind of result applies yet
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 · XV74C1N1AE · read 2026-08-29
Its recorded molecular formula is C6H6O2, weighing 110.11.
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · 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.
No statement of the main limit is recorded.
The four opening statements run to 54 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.
Formulation
A formulation is the exact made-up form a substance comes in.
A picture of it, and where the picture fails
It is like the difference between a whole bean and instant coffee.
Where that stops being true. Coffee tastes different. A formulation can change how much reaches the blood.
What people get wrong. Two products with the same name are assumed to behave the same. They often do not.
The specific composition and physical form of a product, including salt, excipients and release profile.
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.
plasma homocysteine level, plasma folate acid and red blood cell folate acid, Framingham risk score
✗ The study did not show it
Who was studied
NCT00755664
How many people
390
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
antipigmenting assessment
✗ The study did not show it
Who was studied
NCT06516224
How many people
150
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
MASI score, at the beginning of the study and at weeks 4, 8 (end of the treatment), 12 and 52.
✗ The study did not show it
Who was studied
NCT01001624
How many people
150
Study design
Phase 3
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
Change in Melasma Area and Severity Index (MASI) Score
✗ The study did not show it
Who was studied
NCT07327983
How many people
146
Study design
Not applicable
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
MASI Score
✗ The study did not show it
Who was studied
NCT07732192
How many people
128
Study design
Phase 4
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
EFFICACY OF COMBINATION OF TAM FORMULA VERSUS KLIGMAN FORMULA IN TREATMENT OF MELASMA
✗ The study did not show it
Who was studied
NCT06013540
How many people
122
Study design
Phase 2
Compared against
Not recorded for this study
Kind of result
A number that stands in for health
What was found
Result not recorded on this page
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. 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. Topical
Interval reported. Not recorded in this summary
Written into the record, not signed off as a reviewed claim.
openFDA Drugs@FDA · a recorded source, not a stored snapshot
openFDA NDC Directory · a recorded source, not a stored snapshot
openFDA SPL label · a recorded source, not a stored snapshot
PubChem PUG-REST · a recorded source, not a stored snapshot
What we know
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 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.
BLEMISH ERASER is a combination of hydrocortisone (a corticosteroid), hydroquinone (a melanin synthesis inhibitor), and a tretinoin (a retinoid) that is indicated for the gradual bleaching of hyperpigmented skin conditions age and liver spots, freckles, and other unwanted areas of melanin hyperpigmentation, in the presence of measures for sun avoidance, including the use of sunscreen.
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: “Safety and effectiveness of BLEMISH ERASER in pediatric patients have not been established.”
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · read 2026-08-30
On older people, the label states: “In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.”
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · read 2026-08-30
On people who are pregnant, the label states: “Teratogenic Effects: Pregnancy Category C In general, use of drugs should be reduced to a minimum in pregnancy.”
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · read 2026-08-30
On people who are breastfeeding, the label states: “Corticosteroids, when systemically administered, appear in human milk.”
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · read 2026-08-30
Where the result stopped carrying
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.
A different form was studied
The studied form is not the form on the shelf.
On this record: This record is linked to 1 related forms. Evidence does not carry across all of them.
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 (10)
It was studied for a different goal
The studies measured something else entirely. 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
Topical
✎ 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
Sold as cream, liquid, lotion, emulsion, given by the topical, oral route.
✎ 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∅Nothing found in the sources checked
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.
∅Nothing found in the sources checked
No harm is recorded against this substance in the sources RNAWiki checked. Finding nothing is not the same as showing there is nothing.
The sources listed were searched and held nothing. That is not the same as nothing existing.
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
✎ 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
Not recorded.
∅ Nothing recorded
Where this came from
RNAWiki holds nothing here and says so rather than guessing.
Nothing further is recorded about which forms are sold.
No source is stored against this line.
What is recorded as being sold
31 products list this as an active ingredient in the United States drug directory. 28 of them contain it and nothing else.
FDA National Drug Code directory · 71399-0400 · read 2026-08-29
They are sold as cream, emulsion, gel, granule, liquid and lotion, taken oral and topical.
FDA National Drug Code directory · 71399-0400 · read 2026-08-29
The regulator's established pharmacologic class for it is depigmenting activity [pe], melanin synthesis inhibitor [epc] and melanin synthesis inhibitors [moa].
FDA National Drug Code directory · 71399-0400 · read 2026-08-29
20 published labels name it as an active ingredient. 17 of them describe this substance alone, which is where its own label text on this page comes from.
US prescribing information · 81e2e734-01fe-4568-903a-92993bf40887 · read 2026-08-29
Those labels are classed as human otc drug and human prescription drug.
US prescribing information · 81e2e734-01fe-4568-903a-92993bf40887 · read 2026-08-29
OLIVIA QUIDO BLEMISH ERASER is topical at 3 DOSAGE FORMS AND STRENGTHS Cream, 2%., recorded as fda label in effect 2022-06-05 in the United States.
US prescribing information · dfc742ae-41b5-d64a-e053-2995a90a1a8f · read 2026-08-30
Recorded price in US: 0.45391–0.51677 USD per one gram, across 3 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.
This order is fixed in code and does not count clicks or time on the page.
What is not here
9 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.
The path through the body — 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.
Claims that go past the evidence — 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.
Recorded evidence blocks (8)
Q1
On the Hydroquinone label: indicated for what?
"HYDROQUINONE 4% CREAM is indicated for the gradual bleaching of hyperpigmented skin conditions such as chloasma, melasma, freckles, senile lentigines, and other unwanted areas of melanin hyperpigmentation.": indications and usage on Hydroquinone's label. DailyMed label · 595dfc50-ee6f-41b5-ab5b-4c293aee342b · 2026-07-10
Q2
18 registered trials of Hydroquinone — at which phases?
Human studies of Hydroquinone used Fluocinolone acetonide 0.1%/hydroquinone 4%/tretinoin 0.05% Cream in sequence with glycolic acid peels — over how long?
Human studies of Hydroquinone used "Fluocinolone acetonide 0.1%/hydroquinone 4%/tretinoin 0.05% Cream in sequence with glycolic acid peels". ClinicalTrials.gov · 2026-09-01
6 recorded entries; human; also "Fluocinolone acetonide 0.01%, hydroquinone 4%, tretinoin 0.05%", "4% hydroquinone", "Hydroquinone 4% Cream"
Show the evidence
human
NCT00472966
Fluocinolone acetonide 0.1%/hydroquinone 4%/tretinoin 0.05% Cream in sequence with glycolic acid peels
NCT00472966, NCT00975312, NCT02095990, NCT02138539, NCT03751163 and NCT03982849, and 4 more
Completion dates
oldest 2007-04; newest 2024-07-11
Show the evidence
Trial
NCT00472966
2007-04
NCT00975312
2009-02
NCT02095990
2014-08
NCT02138539
2014-10
NCT03751163
2017-04-02
NCT03982849
2020-01-15
4 further recorded trials
NCT04345094
2020-02-15
NCT05511948
2023-03-07
NCT06787846
2024-03-12
NCT06957834
2024-07-11
Q6
At the median, Hydroquinone's trials enrolled 50 people — anything larger?
Median enrolment
50
Largest enrolment
120
Registered trials counted
18
Q7
What do 109 spontaneous reports say about Hydroquinone — 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.
Hydroquinone appears in spontaneous reports to regulators. Across the 8 most-reported reaction terms, 109 reaction mentions were counted: squamous cell carcinoma of skin 34; erythema 17; skin atrophy 16; neoplasm skin 10. FAERS via Open Targets · CHEMBL537 · 2026-06-24
Show the evidence
squamous cell carcinoma of skin
34
erythema
17
skin atrophy
16
neoplasm skin
10
ochronosis
10
skin irritation
8
2 more recorded rows
skin burning sensation
7
skin hyperpigmentation
7
recorded 2026-06-24 · last checked 2026-09-04
Q8
Which 8 reactions does Hydroquinone's label not list?
Black and white bleaching cream, tri-luma cream, Hydroquinone cream
Development code
CHEBI:17594, CHEMBL537, NCI-C55834, NSC-9247
Trade name
Eldopaque forte, Eldoquin forte, Hydroquinone component of tri-luma, Solaquin forte, Obagi-C Rx System C-Therapy Night Skin Lightening with Vitamins C and E, Obagi-C Rx System C-Clarifying Serum Normal To Oily Skin Lightening Serum with Vitamin C, Zo Skin Health Pigment Control Plus Brightening Creme Hydroquinone Plus Vitamin C, Zo Skin Health Pigment Control Plus Blending Creme Hydroquinone, Zo Skin Health Pigment Control Creme Hydroquinone, Obagi C Rx System C Clarifying Serum, Hydro-Q, OLIVIA QUIDO BLEMISH ERASER
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
✗ 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.