What is Melanotan II researched for?

Melanotan II is described in the source as a synthetic alpha-MSH analog. It is associated with skin darkening, erections, and appetite blunting, and it served as a development template for bremelanotide (PT-141). The source distinguishes Melanotan II from approved drugs and states that Melanotan II itself is not FDA or EMA approved.

How does Melanotan II work?

The source describes Melanotan II as a non-selective melanocortin receptor agonist that interacts with MC1, MC3, MC4, and MC5. MC1 activity in pigment cells is linked with melanin production, while MC4 activity in the brain is linked with sexual arousal pathways rather than the vascular pathway targeted by PDE5 inhibitors.

Is Melanotan II FDA approved?

No. The source lists Melanotan II as not FDA approved and notes a restricted FDA Category 2 status, with safety concerns including melanoma risk. It also states that research was discontinued because of side effects.

What side effects or cautions are reported?

The source reports nausea, facial flushing, fatigue, spontaneous penile erections, darkening of skin and moles, priapism, melanoma risk association, and possible histamine-release concerns for people with MCAS or histamine sensitivity. It also flags legal restrictions in the US, UK, and Australia.

What dose does the source report?

The source reports community dosing of 250-500 mcg daily during a loading period, followed by 500-1,000 mcg weekly for maintenance, with a stated range of 100-1,000 mcg per dose and subcutaneous injection as the administration route. These are source-reported research/community values, not dosing guidance.

Sexual Health Research - early research

Melanotan II

Also known as: MT-II, MT2, Melanotan 2

At a glance

PeptiGuide dataset · reviewed Aug 2026

What it is

Synthetic alpha-MSH analog researched for tanning, libido, and erectile function.

Status

Research

Evidence level: early research

Typical dose

250–500mcg

Subcutaneous injection

Researched for

Tanning, libido enhancement, erectile function

Trial progress

PrePreclinical
IPhase I
IIPhase II
IIIPhase III
IVPhase IV
FDAFDA approved

Preclinical - Limited evidence and no established human dosing

Use the tools

In plain language

Synthetic alpha-MSH analog associated in the source with tanning, erections, and appetite blunting.
Not FDA approved; source also states it is not EMA approved and is listed as FDA Category 2 restricted because of melanoma risk and other safety concerns.
Evidence level is limited research, with a trial-phase label in the source dataset.
Source-reported typical dose: 250-500 mcg daily during loading, then 500-1,000 mcg weekly for maintenance by injection.
Researched for tanning, libido enhancement, and erectile function.

How it's thought to work

Melanotan II is reported as a broad melanocortin receptor rather than a receptor-selective compound. The source names MC1, MC3, MC4, and MC5 as targets. MC1 signaling in melanocytes is tied to melanin production, while MC4 signaling in the central nervous system is linked to sexual arousal and desire pathways. The broad receptor profile is also presented as a reason for a wider adverse-effect profile.

What the research shows

Where the research stands

The supplied research summary describes narrow older human evidence for erectile-function outcomes. In men with organic erectile dysfunction, the source reports subjectively described erections after 12 of 19 Melanotan II injections compared with 1 of 21 placebo doses, plus longer rigidity periods and greater sexual interest; nausea and yawning were frequent. The source connects this effect profile to later bremelanotide development. For tanning, the same source emphasizes lack of large safety trials and dermatology concerns including changing moles, melanoma reports, uneven or lasting pigmentation changes, nausea, and risks from unregulated injected material.

What it shows

✓ Early research

Limited evidence and no established human dosing

△ Limitations

Early research findings may not translate directly to human outcomes.

Bottom line: Not approved; research reportedly discontinued due to side effects. Source also lists FDA Category 2 restricted status tied to melanoma risk and other safety concerns. Not FDA Approved

Typical dosing

CommunityCommunity dataset

250–500 mcg

daily (loading), then 500-1,000 mcg weekly (maintenance)

100 mcgfull range seen1,000 mcg

Community-reported dosing only. Source cautions that initial nausea is common, tanning and libido effects may occur, and UV exposure was noted as part of the tanning context. · Subcutaneous injection · Loading 1-2 weeks, then maintenance

Research dosing

Early researchEarly research - limited data

Doses observed in studies

250-500 mcg initially

Research Literature - Observed in studies

Early research findings may not translate directly to human outcomes.

Duration: Loading phase 2-3 weeks, then maintenance
Administration: Subcutaneous injection

Timing & administration

Best time to take

Evening or before sun exposure

Once daily during loading, then maintenance

Food recommendation

With or without food

Why this timing?

The source ties evening timing to reducing visible flushing and pre-sun timing to tanning-oriented use; this is source-reported context, not a use recommendation.

Possible side effects

Not everyone experiences these. Individual responses vary with dose, duration, and personal factors.

Nausea
Facial flushing
Fatigue
Spontaneous penile erections
Darkening of skin and moles
Priapism
Association with melanoma risk
Possible histamine release
Legal restriction caution

Not everyone experiences side effects, and severity can vary by context, purity, route, and individual health factors.

Sources

PubMed ClinicalTrials.gov FDA.gov

Frequently asked questions

Sequence

Ac-Nle-Asp(1)-His-D-Phe-Arg-Trp-Lys(1)-NH2; Asp3-Lys8 lactam

One open dataset

Every fact on this page - doses, side effects, references - comes from the same PeptiGuide dataset that powers the Tracker, Compare, and the Lab.

Browse the dataset

Save to my research list Get updates on Melanotan II

Educational resource, not medical advice. Talk to your clinician before acting on anything here.

Community discussion

Comments are moderated before they appear. Keep it evidence-focused.

Melanotan II

In plain languageIn plain language

How it's thought to workHow it's thought to work

What the research showsWhat the research shows

Typical dosing

Research dosing

Timing & administrationTiming & administration

Possible side effectsPossible side effects

SourcesSources

Frequently asked questionsFrequently asked questions