Melanotan I
Melanotan-1, MT-I, MT-1, CUV1647, Nle4-D-Phe7-α-MSH, Scenesse, EI-_05x (Epitan), afamelanotide
Checked Oct 28, 2026
The short answer
Human-trial signal for sunless tanning in healthy adults (injectable)
Grade B for tanning, result worked: one randomized placebo-controlled trial of 28 men in 1991 showed skin darkening and none on placebo.
- Approved?
- Approved for: erythropoietic protoporphyria, to increase pain-free light exposure in adults (FDA, 2019; EMA, 2014).
- Safety: B, characterized
- In the approved implant, implant-site reactions (21% vs 10% on vehicle) and nausea (19% vs 14%) were most common and the label warns of serious hypersensitivity including anaphylaxis, but injectable vials sold online have unverified identity and purity and long-term melanoma risk with off-label use is unknown.
The full answer: what it is for, the dose, the units
What people take it for: Most people take the injectable to tan without sun. The approved product is a different thing: a 16 mg implant placed by a clinician for erythropoietic protoporphyria (EPP), a rare light-sensitivity disease.
Does it work for sunless tanning in healthy adults (injectable)? B, human-trial signal. Result: worked.
Grade B for tanning, result worked: one randomized placebo-controlled trial of 28 men in 1991 showed skin darkening and none on placebo. For EPP it is grade A, from two Phase 3 trials and FDA approval, and that does not carry over to tanning.
Approved for: erythropoietic protoporphyria, to increase pain-free light exposure in adults (FDA, 2019; EMA, 2014). That does not carry over to tanning. The approved product is a 16 mg implant placed by a clinician, not the injectable vials sold for tanning, and no agency has approved it for tanning or vitiligo. FDA Drugs@FDA, SCENESSE (afamelanotide) NDA 210797, approved 2019-10-08
Highest evidence for any use: A for pain-free light exposure in erythropoietic protoporphyria.
Safety: B, characterized. In the approved implant, implant-site reactions (21% vs 10% on vehicle) and nausea (19% vs 14%) were most common and the label warns of serious hypersensitivity including anaphylaxis, but injectable vials sold online have unverified identity and purity and long-term melanoma risk with off-label use is unknown.
Do not use if: Approved only for adults; contraindicated after a severe hypersensitivity reaction to afamelanotide or its excipients.
Could it be placebo? Trials for this use beat placebo on skin darkening, a measured outcome, but the tanning trial was small (28 men) and short, so it does not show how well it works in everyday users.
The dose people use, and the units to draw
The approved implant is 16 mg every 2 months; human studies of the injectable gave 0.08 to 0.21 mg/kg per dose under the skin, and no named non-seller source gives a self-use dose.
| Source | Dose | How often and how | Who it was for | Link |
|---|---|---|---|---|
| SCENESSE (afamelanotide) US prescribing information | One 16 mg implant | Every 2 months, subcutaneous implant above the anterior supra-iliac crest, placed by a trained health care professional | Adults with a history of phototoxic reactions from erythropoietic protoporphyria (EPP); the only approved use | Indications; Dosage and Administration |
| Langendonk et al., NEJM 2015 (two Phase 3 RCTs) | 16 mg implant | Subcutaneous implant every 60 days; EU trial 5 implants (days 0 to 240), US trial 3 implants (days 0 to 120) | 74 (EU) and 94 (US) adults with EPP, randomized 1:1 to afamelanotide or placebo implant; median pain-free sun hours 6.0 vs 0.8 (EU, P=0.005) and 69.4 vs 40.8 (US, P=0.04) | Methods (dosing schedule); Results (primary end point) |
| Levine et al., JAMA 1991 (randomized, double-blind, placebo-controlled) | Per-injection dose not stated in the abstract or record page opened | 10 subcutaneous injections over 12 days, then 7 weeks of follow-up; all used high-potency sunscreen | 28 healthy white men (skin types I to IV); significant skin darkening vs no darkening on placebo, peak 1 to 3 weeks after the last injection | Abstract |
| Ugwu et al., Biopharm Drug Dispos 1997 (pharmacokinetic trial) | 0.08 to 0.21 mg/kg per dose subcutaneous (0.16 mg/kg IV and oral comparators) | Randomized crossover, 5 consecutive days for 2 weeks, 10 doses total | 3 healthy men; subcutaneous dosing fully bioavailable, no detectable level after oral dosing, tanning after IV or subcutaneous dosing | Abstract |
| Dorr et al., Photochem Photobiol 2000 | 0.16 mg/kg per day | Subcutaneous injection, Monday to Friday for 2 weeks (10 doses); open-label | 7 healthy volunteers (6 men, 1 woman), skin types III or IV; tanning at 3 of 8 sites, forearm eumelanin up about 98% one week after | Abstract |
| Dorr et al., Arch Dermatol 2004 (three open-label Phase 1 studies) | 0.08 mg/kg per day (study 1) and 0.16 mg/kg per day (studies 2 and 3) | Daily for 10 days with UV-B exposure (studies 1 and 2); study 3 combined with sunlight 5 days a week for 4 weeks. Route stated as subcutaneous for study 1 only in the abstract | 8, 12 and 8 healthy volunteers; more tanning than controls, which needed about 50% more sun exposure in study 3 | Abstract |
Human studies of the injectable gave 0.08 mg/kg (Dorr 2004, study 1) up to 0.21 mg/kg per dose (Ugwu 1997), while the approved implant is a fixed 16 mg every 2 months for EPP only.
Searched for Huberman Lab, Attia and Examine mentions and found none with a dose for afamelanotide or Melanotan 1. The Levine 1991 per-injection dose is not in the abstract page opened. Self-use ranges printed before came only from vendor and forum sites and are removed; no named non-seller source gives a self-use dose. The prior text cited a 1996 study for 0.16 mg/kg/day, but PMID 8637402 is a Melanotan II study; 0.16 mg/kg/day is from Dorr 2000 and Ugwu 1997.
Reported by the named source, never prescribed by us.
How many units do I draw?
Use the calculator: concentration in mg per mL is vial mg divided by water mL, and units on a U-100 syringe are dose mg divided by concentration, times 100. Open the dose calculator
Why it might work
Synthetic linear analogue of α-melanocyte-stimulating hormone (α-MSH); agonizes the melanocortin-1 receptor (MC1R) on melanocytes, driving eumelanin synthesis independently of UV, plus antioxidant, DNA-repair-enhancing, and anti-inflammatory effects. Substitutions (Nle4, D-Phe7) make it ~resistant to enzymatic degradation, giving a far longer half-life than native α-MSH. Mechanism is established (approved drug), not assumed.
The trials, claim by claim
The A grade is for erythropoietic protoporphyria only. The headline use here, tanning, is graded B on one small randomized trial.
FDA-approved (Oct 8, 2019) as the SCENESSE 16 mg subcutaneous implant to increase pain-free light exposure in adults with a history of phototoxic reactions from erythropoietic protoporphyria (EPP).
Result: worked
FDA approval based on two randomized, double-blind, placebo-controlled phase III trials. EMA-approved since 2014. Orphan/rare-disease indication.
FDA Drugs@FDA. SCENESSE (afamelanotide) NDA 210797In the U.S. phase III RCT, median pain-free direct-sunlight exposure was 69.4 h with afamelanotide vs 40.8 h placebo (P=0.04); the EU trial showed 6.0 h vs 0.8 h (P=0.005) over the study period.
Result: worked
Two multicenter double-blind placebo-controlled RCTs, n=168 total (86 drug / 81 placebo), published NEJM 2015;373:48-59. Quality-of-life and phototoxic-reaction secondary endpoints also favored drug.
PubMed. Langendonk et al., NEJM 2015, Afamelanotide for EPPOff-label/cosmetic tanning: it darkens skin without UV in healthy volunteers. A 1991 randomized, double-blind, placebo-controlled trial of 28 men showed darkening with none on placebo; later human work is small open-label studies of 3 to 12 people, and there is no long-term safety trial for this use.
Result: worked
One randomized, double-blind, placebo-controlled trial (Levine JAMA 1991, 28 men, PMID 1658407) plus small open-label studies (Ugwu 1997, 3 men; Dorr 2000, 7 people; Dorr 2004, 8 to 12 per study). Nothing is approved for cosmetic tanning; gray-market injectable MT-I is unregulated and often mislabeled vs Melanotan II.
PubMed. Ugwu et al. 1997, Skin pigmentation and pharmacokinetics of melanotan-I in humans (3 men)Investigational for vitiligo (with NB-UVB) and previously trialed for polymorphous light eruption. The vitiligo phase III (CUV105, about 210 patients) has finished enrolling and the company expects topline results in December 2026; a pivotal phase III (CUV107) is planned to start in November 2026.
Active and prior company-sponsored phase III programs; vitiligo data not yet reported (company guidance: December 2026), PLE program did not yield approval. Promising but unproven for these uses.
ClinicalTrials.gov NCT06109649, CUV105 vitiligo Phase 3SCENESSE carries a US warning for serious hypersensitivity reactions, including anaphylaxis, reported after approval.
Stated in the current FDA-approved label (added by a labeling supplement approved August 12, 2024). Label fact, not an efficacy claim.
DailyMed. SCENESSE labelSexual side effects (spontaneous erections, libido changes) belong to Melanotan II, not Melanotan I, a key confound, since gray-market vendors and forums routinely mix up or mislabel the two.
MT-II is the cyclic non-selective melanocortin agonist responsible for the famous self-injection erection anecdote and PT-141/bremelanotide lineage; MT-I (linear, MC1R-predominant) is not associated with sexual effects per clinical reports.
PubMed search, melanotan adverse effects reviewRisks and the label warnings
Adverse events
In the regulated implant (US label, through month 6): implant-site reactions 21% vs 10% on vehicle (mainly discoloration/pain/erythema/hematoma), nausea 19% vs 14%, plus oropharyngeal pain, cough, fatigue, dizziness, somnolence, and skin hyperpigmentation (4% vs 0%). Generalized skin darkening and darkening/new melanocytic nevi occur, full-body skin exams are advised twice yearly. No drug-related serious adverse events in the pivotal trials.
Contraindications
Approved only for adults; contraindicated after a severe hypersensitivity reaction to afamelanotide or its excipients. Since August 2024 the US label also warns of serious hypersensitivity, including anaphylaxis (reported after approval), so patients are watched for 30 minutes after the implant. Hepatic/renal impairment not formally studied (caution). The label asks for a full-body skin exam twice yearly. Not indicated or studied in pregnancy/lactation. As an implant, requires trained in-office insertion.
Theoretical concerns
Because MC1R agonism darkens existing nevi and stimulates melanocytes, there is a theoretical (unquantified) concern about masking or promoting melanoma; long-term carcinogenicity data are limited and monitoring is mandated rather than reassured. Generalized hyperpigmentation is cosmetically irreversible until the drug clears.
What nobody knows yet
The dominant real-world risk is NOT the approved drug, it is the gray-market injectable 'Melanotan 1' sold online and in gyms: unverified identity/purity, frequently conflated with or substituted by Melanotan II (which adds nausea, priapism, and cardiovascular effects), non-sterile reconstitution, and self-injection. Long-term melanoma risk of chronic off-label use is genuinely unknown.
What else could explain the result
Three big confounds: (1) MT-I vs MT-II conflation, sexual side effects, the worst safety case reports (priapism, rhabdomyolysis, AKI, renal infarction, melanoma case reports), and 'fat loss/libido' claims belong to non-selective MT-II, not MT-I; (2) the FDA halo, grade A is for EPP photoprotection, not for cosmetic tanning, where evidence is one small randomized trial and a few open-label volunteer studies; (3) tanning is self-reinforcing, users sun-expose more, which independently darkens skin, inflating perceived drug effect.
Is the vial what it says?
Approval verified against FDA Drugs@FDA (NDA 210797, approved 2019-10-08) and DailyMed/EMA labeling; efficacy verified against the peer-reviewed NEJM 2015 phase III RCT (PMC4780255) with exact endpoints and p-values; tanning evidence verified against the original small human studies (Levine JAMA 1991; Ugwu et al. 1997, PMID 9113347). Adverse-event percentages cross-checked between FDA review and EMA SmPC. MT-I vs MT-II distinction verified across DermNet and review literature.
Half-life and storage
Half-life: Apparent half-life ~15 hours from the controlled-release SC implant; median Tmax ~36 h, mean Cmax ~3.7 ng/mL. Drug is generally undetectable in plasma within ~2-3 days of implant placement, while the pigmentation effect persists for weeks (hence the 2-month dosing interval). Native α-MSH, by contrast, degrades within minutes.
Once mixed: The approved product is a solid bioresorbable implant (no reconstitution). For gray-market lyophilized injectable powder, peptide-handling norms apply: reconstitute gently with bacteriostatic water, do not shake, refrigerate after mixing, protect from light and heat. Reconstitution quality is unverifiable for unregulated product, which is itself a core risk.
What I noticed, and what people report
What people report
Volume of reports: mixed. Reports exist but contradict each other.
Moderate-to-high chatter, but skewed: most online volume is about Melanotan II (the stronger tanning + libido peptide) and PT-141, with MT-I discussed comparatively less and frequently confused with MT-II. EPP-patient communities (e.g., porphyria foundations) discuss the approved drug seriously and separately from the tanning crowd.
Mixed/inconsistent. EPP patient and clinical sources are consistent and positive about real benefit. The tanning-forum signal is muddier: users agree MT-I tans more slowly and 'cleaner' than MT-II (fewer side effects) but many find it underwhelming versus MT-II and pivot to the stronger compound, so the cosmetic signal partly self-selects toward its sibling.
Two-tier. High-credibility: peer-reviewed trials, FDA/EMA, and disease-foundation sources for the EPP indication. Low-credibility: most tanning-peptide vendor sites and 'peptide wiki' pages are affiliate/commercial, conflate MT-I and MT-II, and recite dosing with no controlled-trial basis, discount these heavily.
- EPP patients and porphyria communities broadly report genuine, life-changing increases in tolerable sun/light exposure, among the most credible positive signals for any peptide, backed by the trials.
- Cosmetic-tanning users say MT-I builds a slower, more natural-looking tan than Melanotan II and lacks the nausea/flush/erection effects, but many find it 'too mild' and switch to MT-II for faster results.
- Recurring complaints across off-label users: new or darkening moles and freckles, uneven pigmentation, and nausea/flushing during loading, plus persistent confusion over whether vendor 'MT-1' is actually MT-2.
- Skeptical/clinical voices repeatedly warn that the gray-market injectable is unregulated, frequently mislabeled, and that long-term melanoma risk is unknown, and that the FDA approval applies only to the EPP implant, not to buying it online to tan.
Reports are anecdote, not proof.
Can you tell if it is working?
Skin melanin index by reflectance colorimetry, read at a UV-shielded site, is the direct objective proof it works, darkening at a covered site can only come from the drug.
Bloodwork
Nothing on a routine panel confirms this one. Anyone who says otherwise is guessing.
Melanotan-1 (afamelanotide) is an alpha-MSH analog and MC1R agonist that drives eumelanin synthesis in skin melanocytes; its therapeutic action is local cutaneous pigmentation/photoprotection, which produces no measurable circulating analyte. In the pivotal EPP randomized trials it did not lower the disease's own biomarker (erythrocyte/plasma protoporphyrin) or alter liver biochemistries, so no routine bloodwork can confirm it is working.
Read this before you spend on labs
Bloodwork cannot verify melanotan-1. Its effect is cutaneous, increased eumelanin (tanning) and, in erythropoietic protoporphyria, longer pain-free sunlight exposure. Response is judged visually / by skin-reflectance and by light-tolerance and phototoxicity symptoms, not by any serum test. No routine LabCorp/Quest analyte reflects melanin synthesis, and in the randomized EPP trials afamelanotide did not lower erythrocyte protoporphyrin, plasma protoporphyrin, or alter liver biochemistries versus baseline, so even the disease's own biomarker does not track efficacy. Track it on the skin and by symptoms, not in a tube.
Other ways to track it
Skin reflectance colorimetry / melanin index (dermatology-grade Mexameter or DSM-II ColorMeter at a clinic; standardized fixed-lighting before/after photos of a sun-shielded site as a lower-fidelity home proxy)
A working result shows a measurable rise in melanin index (a darker reflectance reading) at a fixed, UV-shielded body site such as the inner upper arm or buttock, with no sun exposure. Because the site is covered, any darkening can only come from the drug, not tanning. This is the actual therapeutic effect, not a proxy for it.
Melanotan-1 (afamelanotide) is an MC1R agonist that drives UV-independent eumelanin synthesis in melanocytes. Increased cutaneous melanin is precisely the effect the drug produces, and reflectance melanin density is the same class of readout used to quantify afamelanotide's effect in human trials, so a colorimeter measures efficacy directly.
Bottom line
The effect is purely cutaneous, and that is exactly why it is trackable: skin melanin index by reflectance colorimetry at a sun-shielded site is a genuine DIRECT objective efficacy readout (the Ground Truth page confirms there is no blood proxy). Nothing in urine, stool, sleep/wearable, CGM, VO2max, or DEXA applies, melanotan-1 does not move metabolic, body-composition, or recovery markers. MC1R genotype was dropped: it is a real and mechanistically sound responder predictor, but it is static and cannot confirm that any given course actually worked, so it is not a tracking channel. If you cannot measure pigmentation at a covered site, you have no objective confirmation.
Logging baseline vs retest is the whole game. The Truth Tracker is our free log for bloodwork, DEXA, genetics, and wearable data, bring your own numbers.
How to track itHistory
First documented human use: First controlled human use 1991 (Levine et al., JAMA. SC α-MSH analogue induced measurable tanning in volunteers); a small pharmacokinetic study in 3 men in 1997 (Ugwu, Blanchard, Dorr). This is one of the few peptides where the question is genuinely settled: pivotal phase III RCTs were completed and the drug is FDA-approved (Oct 8, 2019, for EPP).
- Early 1980sSynthesized at University of Arizona (Hruby, Hadley, Levine) as a stable α-MSH analogue; hypothesis was a UV-free protective tan to reduce skin-cancer risk.
- 1991First controlled human demonstration of induced tanning via SC α-MSH analogue (Levine et al., JAMA).
- 1997A small pharmacokinetic study in 3 men (Ugwu, Blanchard, Dorr) describes subcutaneous absorption and skin pigmentation.
- 2005-2006Licensed to Australian biotech Epitan, which renamed to Clinuvel; compound designated CUV1647, then INN 'afamelanotide.'
- 2007-2011Phase II/III program in EPP (and PLE); pivotal EU trial Jan 2010-May 2011, U.S. trial May 2012-Jul 2013.
- 2014EMA approval as SCENESSE for EPP in the EU.
- Jul 2015Pivotal phase III RCT results published in NEJM.
- Oct 8, 2019FDA approves SCENESSE implant for EPP, first approved treatment for the disease.
- Sep 2025EMA removes the four-implants-per-year cap; one implant every two months is allowed year-round.
- Dec 2026 (expected)Company guidance for CUV105 vitiligo topline results; pivotal CUV107 planned to start Nov 2026.
All sources
- FDA Drugs@FDA. SCENESSE (afamelanotide) NDA 210797(Primary regulatory record; FDA approval 2019-10-08 for EPP.)
- DailyMed. SCENESSE (afamelanotide) implant label(Official prescribing information: indication, dosing, adverse reactions, monitoring.)
- PubMed. Langendonk et al., NEJM 2015, Afamelanotide for EPP (phase III RCTs)(Pivotal double-blind placebo-controlled trials; exact endpoints and p-values.)
- PMC. Afamelanotide for EPP, full text (PMC4780255)(Open-access full trial report with detailed results and adverse events.)
- PubMed. Ugwu et al. 1997, Skin pigmentation and pharmacokinetics of melanotan-I in humans (3 men)(Original human PK/tanning data; anchors first-human-use and dosing history.)
- ClinicalTrials.gov NCT06109649, CUV105 vitiligo Phase 3(Registry record for the ongoing vitiligo phase III; the EPP pivotal trials are in the NEJM report above.)
- PubMed. Kim and Garnock-Jones 2016, Afamelanotide: A Review in EPP (Am J Clin Dermatol)(Independent drug review summarizing efficacy/safety.)
- NCBI LiverTox. Afamelanotide(NIH safety monograph; hepatotoxicity and class context.)
- DermNet NZ. Melanotan(Clinical dermatology source distinguishing MT-I vs MT-II and gray-market risks.)
- DailyMed. SCENESSE (afamelanotide) implant label, Indications and Dosage and Administration; FDA approval 2019-10-08 (NDA 210797)(dose table)
- Langendonk JG et al. N Engl J Med 2015;373(1):48-59. PMID 26132941. DOI 10.1056/NEJMoa1411481(dose table)
- Levine N et al. JAMA 1991;266(19):2730-2736. PMID 1658407. DOI 10.1001/jama.1991.03470190078033(dose table)
- Ugwu SO et al. Biopharm Drug Dispos 1997. PMID 9113347(dose table)
- Dorr RT et al. Photochem Photobiol 2000;72(4):526-532. PMID 11045725(dose table)
- Dorr RT et al. Arch Dermatol 2004;140(7):827-835. PMID 15262693. DOI 10.1001/archderm.140.7.827(dose table)
Not medical advice. Grades reflect the evidence as of the date above and will change as data arrives. Reports from users are anecdote, not proof. Talk to a licensed clinician before you act on anything here.