Melanotan II (10 mg vial)

Protocol Overview

Concise summary of the regimen.

Dosing & Reconstitution

Injections are subcutaneous and given in the evening. Evening dosing is the standard because nausea peaks 30 to 90 minutes after the injection, and sleeping through that peak reduces the subjective burden. Daily dosing applies only to the loading block; once maintenance begins the cadence is once every 1 to 2 weeks, not daily. UV exposure, natural sun or a controlled bed, is required for visible tanning expression, because Melanotan II raises melanogenesis capacity but pigment still needs a UV stimulus to develop. The community loading doses used here, 250 to 500 mcg, sit 2 to 3x below the effective tanning doses in the Dorr 1996 trial of 700 to 1,750 mcg; that gap reflects a deliberate nausea-minimization trade-off rather than an evidence-based optimization. Tachyphylaxis of the anorectic effect develops with chronic use, which limits any appetite-suppression utility over time. At draws of 2.5 to 5 units, a 0.3 mL 30 unit or 0.5 mL 50 unit U-100 syringe reads far more clearly than a 100 unit barrel. Sites are rotated across abdomen, thighs, and upper arms.

Results Timeline

Sequence described in the research record. Individual response varies.

• Day 1: a single 250 mcg tolerance test (2.5 units) in the evening, which establishes nausea tolerance before any daily dosing begins.
• Loading, 1 to 4 weeks: 500 mcg (5 units) daily in the evening, with fair skin running the full 3 to 4 weeks, medium skin about 2 weeks, and darker skin about 1 week.
• Across loading: controlled UV exposure is what converts melanogenic capacity into visible pigment, and nausea and flushing typically decline as the block continues.
• Maintenance: 500 mcg (5 units) weekly to biweekly, which holds pigment without any return to daily dosing.
• Course end: use is self-limiting rather than chronic, and a dermatology check follows the course just as one preceded it.

Reconstitution Steps

1. Draw 1.0 mL bacteriostatic water with a sterile syringe.
2. Inject slowly down the vial wall; avoid foaming.
3. Gently swirl until dissolved (do not shake).
4. Label with date and concentration; refrigerate at 2 to 8 °C, protected from light. At 10 mg/mL, 1 unit = 0.01 mL » 100 mcg on a U-100 insulin syringe: 250 mcg = 2.5 units, 500 mcg = 5 units.
5. At draws this small, a 0.3 mL 30 unit U-100 syringe makes the 2.5 unit tolerance dose readable; a 100 unit barrel does not.

Storage Instructions

Proper storage preserves peptide quality.

• Lyophilized: store at minus 20 °C (minus 4 °F) in dry, dark conditions, where the powder stays stable for 12 or more months.
• Reconstituted: refrigerate at 2 to 8 °C (35.6 to 46.4 °F) whenever not in use, and never refreeze the solution, since freeze-thaw cycles degrade the peptide.

• Allow vials to reach room temperature before opening, which reduces condensation uptake into the powder.
• Protect the vial from light and inspect the solution before each draw; discard anything discolored, cloudy, or carrying visible particulate.

Supplies Needed

Planning is based on a 250 mcg day 1 tolerance test, then 500 mcg daily loading, which is 3.5 mg per week across a block of 1 to 4 weeks, followed by 500 mcg weekly to biweekly maintenance for 8 to 12 weeks.

Peptide Vials (Melanotan II, 10 mg vial):

• A 2 week loading block plus 8 weeks of maintenance uses about 8.75 mg on biweekly maintenance, which one 10 mg vial covers, or about 10.75 mg on weekly maintenance, which crosses into a second vial for the last dose or two. A 4 week loading block plus 12 weeks of maintenance uses about 19.75 mg, which is 2 vials.

Insulin Syringes (U-100):

• Per week during loading: 7 U-100 insulin syringes, one per daily injection; maintenance runs 1 syringe every 1 to 2 weeks.
• Full cycle: 18 to 22 syringes for a 2 week loading block plus 8 weeks of maintenance, and 34 to 40 syringes for a 4 week block plus 12 weeks, depending on whether maintenance is weekly or biweekly.

Bacteriostatic Water (10 mL bottles):

• Each 10 mg vial takes 1.0 mL of bacteriostatic water, so one 10 mL bottle reconstitutes 10 vials, far more than either cycle length requires.

Alcohol Swabs:

• Per injection: 2 alcohol swabs, one for the vial stopper and one for the skin.
• Full cycle: 36 to 80 swabs depending on loading length and maintenance cadence, so a single 100 count box covers it.

Important Notes

Practical considerations for consistency and safety.

• Non-selective receptor activation is the core safety issue. Melanotan II activates MC1R in skin, MC3R in energy homeostasis, MC4R for appetite and sexual arousal, and MC5R in exocrine tissue, and it crosses the blood-brain barrier, so tanning, appetite, and erectile effects co-occur. Melanotan I (afamelanotide) is the FDA-approved comparator: same parent molecule, linear instead of cyclic, MC1R-selective, no blood-brain barrier crossing, given as a 16 mg implant every 60 days by a specialist physician, with 1,000 or more patients over 10 or more years and zero melanoma events.
• The day 1 tolerance test is not optional. Nausea is dose-dependent, and 13% of subjects experienced severe nausea at the higher Dorr trial doses. Evening dosing is essential because nausea peaks 30 to 90 minutes after injection. Serious adverse events are documented at supratherapeutic doses far above this protocol: rhabdomyolysis after a 6 mg single injection (CPK 17,773 IU/L, ICU admission), renal infarction at roughly 27 mg cumulative over 6 months, and priapism with overdose. Those figures underscore the danger of unregulated self-dosing rather than of the 250 to 500 mcg range itself.
• UV exposure is required for visible tanning expression. Without controlled UV the dose is wasted, and with uncontrolled UV the real skin cancer risk, which is UV damage rather than MC1R activation, compounds. MC1R activation itself is photoprotective rather than oncogenic: an Addison's disease cohort of 3,299 patients followed for 40 years showed melanoma incidence numerically below expected, and all five melanoma case reports in Melanotan II users involved confounding factors such as tanning bed use, fair skin, or familial risk.
• There is a documented dermatologic risk signal even so: mole darkening, eruption of new nevi including dysplastic histology, and melanonychia (dark nail bands) are reproducibly documented across case series. An annual full-body dermatology check before, during, and after use is strongly recommended. Contraindications include personal or family history of melanoma, multiple atypical or dysplastic nevi, FAMMM syndrome, MC1R loss-of-function variants (R151C, R160W, D294H), pregnancy or breastfeeding, and concurrent tanning bed use without medical supervision.
• Product quality is the single biggest risk in the gray market. An Imperial College London analysis of 10 tanning kits found products containing 100 or more unidentified ingredients, LegitScript testing showed 41% of products contaminated or mislabelled, and 68% of adverse event reports involved unlicensed vendors. Source matters more than dose. Nasal tanning sprays are a separate problem: no published clinical trial has used the intranasal route, bioavailability is substantially lower and more variable than subcutaneous, and flavored versions are marketed at younger demographics, which UK CTSI compares to the disposable vape epidemic.
• Regulatory Note: Melanotan II has been FDA Category 2 since 2023 and is illegal to sell in the US, UK, and Australia. It is not DEA-scheduled, so possession is not criminalised in the US. It is expected to remain restricted following the February 2026 HHS partial reversal of Category 2 peptide bans, given the cardiovascular risk profile and the melanoma case-report signal. It has never completed Phase III for any indication. Its legitimate descendants are approved where it is not: bremelanotide (PT-141, Vyleesi) for hypoactive sexual desire disorder and afamelanotide (Scenesse) for erythropoietic protoporphyria. The master sheet does not record a WADA classification for this compound. Supplied for research use only, not for human consumption.

How This Works

Melanotan II is a cyclic 7-residue lactam-bridged analog (Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH2) derived from the active core of alpha-MSH. The cyclization confers enzymatic stability and enough lipophilicity to cross the blood-brain barrier, but it also eliminates receptor discrimination. The peptide activates MC1R, MC3R, MC4R, and MC5R with sub-nanomolar to low-nanomolar affinity, and does not activate MC2R, so there is no cortisol release. MC1R activation on melanocytes drives eumelanin synthesis, the brown-black pigment that absorbs UV, and enhances nucleotide excision repair of UV-induced DNA damage; that is the photoprotective mechanism. MC3R modulates energy homeostasis and contributes to erectile signaling. MC4R activation in the hypothalamus mediates appetite suppression and sexual arousal, and this CNS-active domain is what distinguishes Melanotan II from Melanotan I. MC5R modulates sebaceous secretion and may contribute to fat breakdown, though clinical significance is uncertain. Pharmacokinetically, subcutaneous absorption is rapid with an absorption half-life of 0.07 to 0.79 hr and an elimination half-life of 0.8 to 1.7 hr, yet melanogenic effects persist for weeks beyond detectable drug levels because epidermal melanin turnover takes time. Tachyphylaxis develops for the anorectic effect on chronic dosing.

Benefits & Side Effects

Observations from the published record.

• Dose-dependent tanning was documented in the Dorr 1996 Phase I study (n=3) at 700 to 1,750 mcg subcutaneously; the lower community doses of 250 to 500 mcg reach the effect with reduced nausea but slower onset.
• Erectile response in the Wessells crossover studies (n=10 to 20): 8 of 10 men with psychogenic ED achieved clinically apparent erections, with mean tip rigidity above 80% for 38 minutes against 3 minutes on placebo (p=0.0045). Efficacy was reduced in organic ED, where vascular pathology limits the MC4R-mediated mechanism. Sexual desire elevation was reported after 68% of doses against 19% of placebo.
• Appetite suppression is central and MC3R and MC4R mediated, reducing meal size, but tachyphylaxis develops with chronic use and limits sustained utility. GLP-1 agonists have a better evidence base, a different mechanism, and FDA approval for that purpose.
• Common side effects: dose-dependent nausea (13% severe at the erectile doses), facial flushing, transient blood pressure elevation, spontaneous erection in males, heightened sexual arousal, and decreased appetite. Nausea and flushing decrease with continued use.
• Dermatologic side effects form a documented signal: mole darkening, new nevi including dysplastic histology, and melanonychia, reproduced across multiple case series. Five melanoma case reports exist in users, all with confounding factors; the most parsimonious reading is that users are a self-selected sun-seeking population whose melanoma risk is more plausibly UV-driven than MC1R-driven.
• This is not a treatment for sexual dysfunction and not a treatment for any medical condition. Bremelanotide (PT-141, Vyleesi) is the FDA-approved MC4R agonist for sexual indications, and no clinical indication for Melanotan II has been pursued through Phase III.

Lifestyle Factors

Complementary strategies for best outcomes.

• Baseline dermatology evaluation before starting, a full-body skin check during use, and a follow-up check after the course. This is non-negotiable where there is any personal or family melanoma history, multiple nevi, or fair skin.
• Controlled UV exposure, meaning graduated sun or supervised UV, is what elicits pigmentation; the uncontrolled tanning bed plus Melanotan II combination is the pattern behind the case-report melanoma signal. SPF discipline matters more during use, not less, because the pigment provides some baseline protection but does not eliminate UV damage and cumulative dose still drives cancer risk.
• Hydration and electrolyte support reduce the nausea burden through the loading phase, and sourcing from quality-verified vendors is the single highest-leverage safety decision given a 41% contamination rate in LegitScript testing.
• No stacking with other MC4R-active compounds such as PT-141, bremelanotide, or setmelanotide, since additive CNS receptor activation runs the wrong direction. Use stops immediately on mole changes, persistent nausea or vomiting, severe headache, or unusual muscle pain given the rhabdomyolysis concern.

Injection Technique

General subcutaneous guidance from clinical best-practice resources.

1. Clean the vial stopper and skin with alcohol; allow to dry.
2. Pinch a skinfold; insert the needle at 45 to 90 degrees into subcutaneous tissue.
3. Do not aspirate for subcutaneous injections; inject slowly and steadily.
4. Wait 5 to 10 seconds before withdrawing; dispose of syringe in sharps container.
5. Rotate sites systematically (abdomen, thighs, upper arms) to avoid lipohypertrophy.

References

Source citations for further reading.

1. Sawyer TK et al. [Nle4, D-Phe7]-alpha-MSH: highly potent alpha-melanotropin (PNAS, 1980).
2. Al-Obeidi F et al. Potent cyclic lactam analogues of alpha-melanotropin (J Med Chem, 1989).
3. Dorr RT et al. MT-II Phase I clinical study, n=3 (Life Sci, 1996).
4. Wessells H et al. Synthetic melanotropic peptide initiates erections in psychogenic ED (J Urol, 1998).
5. Langendonk JG et al. Afamelanotide (MT-I) Phase III for EPP (NEJM, 2015).
6. Bohm M et al. Overview of benefits and risks of chronic MC1R activation (JEADV, 2025).