Non-selective melanocortin receptor agonist peptide (unapproved)
Melanotan 2
A melanocortin peptide producing skin darkening and sometimes libido effects; not approved and associated with significant side effects.
- Evidence:
- Limited human evidence
- Status:
- Not FDA-approved
- Reviewed:
- 2026-08-03
Also known as: MT-II, Melanotan 2
What is Melanotan 2?
A melanocortin peptide producing skin darkening and sometimes libido effects; not approved and associated with significant side effects.
This profile is educational. It organizes publicly discussed research context for Melanotan 2 and related naming aliases — it is not a treatment guide.
Proposed mechanism
Agonizes MC1R (tanning), MC3R/MC4R (appetite, sexual function), causing melanogenesis and central melanocortin effects.
Mechanism language on PepGuide describes how researchers discuss pathways. Proposed mechanisms can change as evidence evolves.
Current research notes
Human evidence grade: Limited human evidence
Preclinical evidence grade: Moderate human evidence
Melanotan II is not FDA approved. FDA has warned against use due to side effects including nausea, blood pressure changes, and mole darkening. Some clinical research explored sexual function (overlap with PT-141 pathway). Sold in unregulated markets. Human evidence for safe cosmetic use is insufficient.
Key uncertainties
- Safe long-term tanning use
- Melanoma surveillance needs
Research areas being studied
- Melanogenesis
- Sexual function research
- Appetite modulation
Being studied for a topic is not the same as proven benefit in that topic. Prefer primary literature for study design, endpoints, and limitations.
Safety & side-effect notes
Reported or discussed adverse effects
- Nausea
- Flushing
- Yawning
- Stretching
- Spontaneous erections
- Mole darkening
Additional risks & considerations
- Nausea
- Hypertension
- Mole changes
- Unknown long-term melanoma risk
- Unregulated products
Regulatory status
Not FDA-approved
Not FDA approved; FDA consumer warnings issued.
Regulatory framing here is educational and can lag policy changes. Check official sources for current status.
Frequently asked questions
What is Melanotan 2?
A melanocortin peptide producing skin darkening and sometimes libido effects; not approved and associated with significant side effects.
How does Melanotan 2 work (proposed mechanism)?
Agonizes MC1R (tanning), MC3R/MC4R (appetite, sexual function), causing melanogenesis and central melanocortin effects.
What is Melanotan 2 being researched for?
Melanotan 2 has been discussed in research contexts including: Melanogenesis, Sexual function research, Appetite modulation.
What does current evidence say about Melanotan 2?
Limited human evidence. Melanotan II is not FDA approved. FDA has warned against use due to side effects including nausea, blood pressure changes, and mole darkening. Some clinical research explored sexual function (overlap with PT-141 pathway). Sold in unregulated markets. Human evidence for safe cosmetic use is insufficient.
What safety considerations are noted for Melanotan 2?
Reported or discussed considerations include: Nausea; Flushing; Yawning; Stretching; Spontaneous erections; Mole darkening; Nausea; Hypertension. This is educational information, not medical advice.
Is Melanotan 2 FDA approved?
Not FDA-approved. Not FDA approved; FDA consumer warnings issued.
References & sources
- FDA Consumer Update (2021). Melanotan II pharmacology and safety concerns. Evidence type: review.
Prefer interactive tools? Open the PepGuide library entry for Melanotan 2 or ask PepGuide AI.
Educational and research information only. PepGuide does not sell or prescribe peptides, diagnose conditions, or provide personalized medical advice. Evidence summaries may include early-stage, animal, or limited human research — none of that is a substitute for primary literature or clinician guidance.