Decapeptide-12 (INCI name), YRSRKYSSWY
A synthetic ten-amino-acid peptide found by screening for blockers of tyrosinase, the enzyme pigment cells use to make melanin. It’s sold in creams to fade dark patches such as melasma.
None of these uses is approved. Uses tested in people come first, then claims that rest on animal studies or user reports.
Trial: tested in people, with the result. Animal: cell or animal studies only. No study: nothing published supports it.
Every compound’s uses, by body system: evidence map, and by condition: conditions A to Z.
Category 2 is FDA’s list of bulk substances that may present significant safety risks in compounding. The 503A bulks list adds substances that pharmacies may compound with. Advisory committee votes are advice; FDA makes the final decision. Sport status follows the WADA Prohibited List in force since January 1, 2026; athletes should confirm with their anti-doping organization. Checked October 5, 2026. Status outside the US checked October 7, 2026 against EMA, MHRA, Health Canada and TGA records. By country: EU, UK, Canada, Australia. Status of every compound.
Decapeptide-12 blocks tyrosinase, the enzyme pigment cells (melanocytes) use to make melanin, by competing with the substance the enzyme normally works on. In lab tests it blocked mushroom tyrosinase about 17 times more strongly than hydroquinone, inhibited human tyrosinase by 25–35%, and cut melanin in human pigment cells by 43% over 7 days without killing them.
AnimalMainly from cell and animal studies; not shown in people.
How much reaches pigment cells through skin is unknown; in a 2021 lab study the plain peptide crossed skin poorly. Whether clinical gains came from it, rather than glycolic acid and sunscreen, is also unknown.
Hantash 2009
Cream with 0.01% (100 ppm) decapeptide-12, twice daily for 16 weeks, on one side of the face.
Ramírez 2013
Regimen of 0.01% decapeptide-12 cream with an antioxidant cleanser, 20% glycolic acid lotion and SPF 30 sunscreen for 16 weeks.
Continuous, shown over 26 weeks
The ways Decapeptide-12 is most often run, each tagged with where it comes from.
Hantash 2009: 5 women with stubborn melasma, peptide on one side and placebo on the other; all improved on the developer’s grading scales. Developer-led and very small.
Ramírez 2013, 33 women: melasma scores 60% lower at 16 weeks, with no control group, so the peptide’s share is unknown.
Applied to dark patches or the whole face, such as the cheeks, forehead and upper lip in melasma. Topical only; never inject it.
Nothing special. Skip it and use the next application as usual.
In a 33-woman open-label study of the full regimen, melasma scores were 36% lower than at the start (Ramírez 2013).
TrialIn the 5-woman pilot, melasma looked about 40% better at 12 weeks and 50% at 16 weeks, as later reported by the developer’s group; the regimen study saw scores 60% lower at 16 weeks.
TrialIn 13 women with sun-related pigmentation, 38.5% went from moderate to clear on a regimen containing it, with no control group (Kassim 2012).
TrialSkin irritation or redness (none reported in the studies, up to 33 women for 16 weeks)
Patch-test first. Stop if it doesn’t settle.
Eye irritation
Keep it out of the eyes. Rinse with water if it gets in.
Infection or harm from injecting a cosmetic product
Never inject topical products; they aren’t sterile.
Stop and see a doctor for a spreading rash, swelling, blistering or hives, eye pain after contact, or any dark spot that grows, bleeds or changes.
The side effects people ask about most, answered one by one. Each answer says where it comes from.
Trial: reported in human studies. Not reported: studied in people and not reported. A side effect that hasn’t been reported can still happen, especially with long or high-dose use. Any of these across every compound: the side-effect finder.
No product label covers decapeptide-12, so these come from human studies and from precautions based on how it works. Most important first.
Precaution: follows from how it works or from a related drug, and hasn’t been tested. This isn’t a complete list: a pharmacist or doctor can check a specific medicine or condition. Every documented interaction, by medicine: drug interactions.
What’s known about pregnancy, breastfeeding, kidney and liver problems, age and surgery. Where nothing has been studied, the row says so.
Precaution: not studied, so the caution follows from how it works or from a related drug. Ages are given as approved or studied; this site never gives doses for children. Across every compound: pregnancy, breastfeeding, kidney disease, liver disease, older adults and surgery.
Usually run on its own.
4 key published human studies, with how many people took part. Animal studies aren’t listed here.
All 5 women, with stubborn melasma and skin type IV (light brown), improved significantly on 10- and 5-point grading scales, with no irritation or allergy; the abstract gives no between-side comparison.
Hantash & Jimenez, J Drugs Dermatol 2009, PMID 19663110
Melasma scores (MASI) fell 36% by week 4 and 60% by week 16 from baseline in Hispanic women, with no adverse events; the peptide’s share can’t be separated.
Ramírez et al., J Drugs Dermatol 2013, PMID 23839199
Of 13 women who finished, 38.5% went from moderate sun-related pigmentation to clear, and the rest improved by one or two grades; all products were well tolerated.
Kassim et al., J Cosmet Laser Ther 2012, PMID 22401652
All 4 people with mild to moderate melasma improved, and 1 cleared completely after 6 weeks.
Hantash & Jimenez, J Drugs Dermatol 2012, PMID 22527440
No ongoing trial of decapeptide-12 is registered, and none has finished recently without publishing its results. Checked on ClinicalTrials.gov, October 7, 2026. Every compound: trials under way.
Human data come from 57 people in four small studies: a 5-woman split-face pilot, a 4-patient case series and two open-label regimen studies (33 and 15 women), two of them led by its developer, who later disclosed stock in the product’s maker. Most paired it with glycolic acid and sunscreen without a control group. Its action rests on cell tests, the plain peptide crosses skin poorly in the lab, and long-term use is untested.
Decapeptide-12 is used on the skin, so the math is a dilution, not a syringe dose.
| Powder | Serum volume | Strength | Percent | ppm |
|---|---|---|---|---|
| 10 mg | 50 mL | 0.2 mg/mL | 0.02% | 200 ppm |
| 10 mg | 100 mL | 0.1 mg/mL | 0.01% | 100 ppm |
| 10 mg | 200 mL | 0.05 mg/mL | 0.005% | 50 ppm |
The tested strength, 0.01%, is 100 ppm: 10 mg of pure peptide in 100 mL of cream or serum. Every studied regimen included daily broad-spectrum sunscreen, and most added a glycolic acid lotion.
Every compound side by side: the half-life chart and the storage chart.
Every compound’s numbers: the identifiers table.
Studied and sold at 0.01% (100 ppm) in finished creams. Pure powder is also sold; 10 mg makes 100 mL at the tested strength. Salt form and net peptide content vary by seller.
A synthetic ten-amino-acid peptide found by screening for blockers of tyrosinase, the enzyme pigment cells use to make melanin. It’s sold in creams to fade dark patches such as melasma.
Decapeptide-12 blocks tyrosinase, the enzyme pigment cells (melanocytes) use to make melanin, by competing with the substance the enzyme normally works on. In lab tests it blocked mushroom tyrosinase about 17 times more strongly than hydroquinone, inhibited human tyrosinase by 25–35%, and cut melanin in human pigment cells by 43% over 7 days without killing them. How much reaches pigment cells through skin is unknown; in a 2021 lab study the plain peptide crossed skin poorly. Whether clinical gains came from it, rather than glycolic acid and sunscreen, is also unknown.
Not approved as a drug in the US or EU; used as a cosmetic ingredient. Cosmetics don’t need FDA approval before sale. Never nominated for FDA’s compounding bulk lists; it isn’t on any of FDA’s 503A or 503B category lists (May 2026 and March 2025 versions).
From human studies (Hantash 2009): Cream with 0.01% (100 ppm) decapeptide-12, twice daily for 16 weeks, on one side of the face. Ramírez 2013: Regimen of 0.01% decapeptide-12 cream with an antioxidant cleanser, 20% glycolic acid lotion and SPF 30 sunscreen for 16 weeks. These are the amounts sources reference, not recommendations.
No product label covers decapeptide-12, so these come from human studies and from precautions based on how it works. Anyone thinking of injecting it: It is a cosmetic ingredient, not made to injectable standards, and has never been tested by injection. People with a changing or irregular dark spot: A fading cream can delay the skin check a changing pigmented spot needs; the studies enrolled only people with diagnosed melasma or sun damage. Anyone mixing pure powder above 0.01%: Studies used 0.01% (100 ppm); stronger mixes haven’t been tested for benefit or safety. The “Who should avoid it” section lists 1 more group.
Before mixing: Freezer (about −20 °C), dry and away from light. After mixing: Finished cream: as labeled, cool and dark. This is common practice; no product label covers it.
No. Not named on the 2026 list. It’s a topical cosmetic ingredient, not a drug of the kind S0 covers. The 2027 list adds peptides to S0’s examples but names no cosmetic ingredients.
Yes. The human studies section lists 4 published studies. The largest, from 2013, included 33 people. Melasma scores (MASI) fell 36% by week 4 and 60% by week 16 from baseline in Hispanic women, with no adverse events; the peptide’s share can’t be separated.
Trial 24 weeks, in 13 women who finished an open-label study of a regimen containing it. In a controlled comparison, 16 weeks in 5 women.
Trial Used in creams and serums. In lab tests the plain peptide crossed skin poorly, while a fatty-acid version and microneedles improved delivery; one patient had it applied during in-office skin abrasion.
No study There’s no label and no overdose data; studies used 0.01% creams. Call Poison Help (1-800-222-1222), or emergency services for severe symptoms.
For the protocol details
For how it works, who should avoid it and the limits of the evidence
For uses, the side-effect questions, special situations, trials, identifiers and status outside the US