Synthetic cyclic alpha-MSH analogue and nonselective melanocortin receptor agonist
MT-2 is an experimental peptide best known for producing darker skin pigment and, in small early studies, erections and increased sexual desire. Those effects are real research signals, but MT-2 is not FDA approved, long-term human safety is unknown, and products sold online may not contain what their labels claim.
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Every structured report adds useful context about research setup, outcomes, and unwanted effects as the community dataset grows.
Publicly anonymous by default. Your account keeps reports editable and helps reduce duplicate submissions.Research at a glance
Depth and confidence summarize the research record—not effectiveness, safety, or a recommendation.
Human administration evidence consists mainly of three tiny 1990s SubQ studies, while current development and safety information includes a registered trial, case reports, and product-quality findings.
Research depth describes how large and mature the overall record is. It does not tell you whether the results were positive.
No approved product, modern confirmatory program, established long-term safety dataset, or validated retail formulation exists.
Confidence describes how reliable and consistent the conclusions are. It can be high for one outcome and low for another.
The strongest evidence type shows what the best-supported conclusions are actually based on.
Human findings are more directly relevant than animal or laboratory results, but they still apply only to the populations and outcomes studied.
Route-specific record
These are exposures used in cited research for a specific route and population—not a suggested amount.
Half-life describes how long it takes the measured amount in the body to fall by half. It is not a dosing recommendation.
Evidence can change by administration method. Findings from one route should not automatically be applied to another.
Evidence boundary: These weight-based exposures came from 1990s experiments involving three or ten men per study. They are not starter amounts, tanning cycles, long-term safety evidence, or validation of materials currently sold as MT-2. Amounts shown describe cited research exposure—not a dosage recommendation.
Practical starting point
Common goals and questions—not recommendations or promises of benefit.
The overview, studies, and source ledger below explain what supports each label—and where the evidence stops.
What the evidence says
Two ten-person placebo-controlled crossover erectile-response studies and one three-person pigmentation Phase 1 pilot.
This is the strongest supported conclusion in the current human evidence—not a summary of every claim made about the compound.
Long-term and repeated-use safety, actual risk of pigmentary or neurologic complications, outcomes outside small male studies, and whether unregulated products match the studied compound.
Keeping the main uncertainty visible prevents an early or promising finding from looking more settled than it is.
The evidence story
Importance shows how much an item changes the evidence story. Quality shows how much confidence the design deserves. A strong negative study can score highly on both.
Importance and quality answer different questions. A rigorous study can be highly important even when it challenges a popular claim.
No results were posted by the July 25, 2026 evidence cutoff.
The report documents temporal exposure before diagnosis and discusses MT-II as a possible risk factor.
Reference-standard mass spectrometry confirmed MT-II in the vial, but measured purity was only 30%.
The report described prolonged ischemic priapism that did not resolve with initial treatment and required surgical decompression.
The authors reported a renal infarction they considered most likely related to MT-II exposure.
Administration and handling
The 1996 pigmentation pilot used monitored subcutaneous study exposures ranging from 0.01 to 0.03 mg/kg. The two erectile-response crossover studies used protocol-defined 0.025 mg/kg subcutaneous exposures with six-hour monitoring. These are descriptions of small historical experiments—not recommended doses, starter doses, cycles, escalation plans, or evidence for current retail products. MT-2 has no FDA-approved consumer route, dose, schedule, indication, or self-administration instructions.
No FDA-approved MT-2 product label or regulator-validated reconstitution and storage standard was identified. Powder, acetate salt, nasal spray, solution, and other seller-labeled forms cannot be assumed interchangeable. A forensic report found only 30% purity in one vial labeled Melanotan II, illustrating why a label cannot establish identity, concentration, sterility, purity, stability, or beyond-use dating. Peptide Relay does not convert vendor directions into official handling guidance.
Primary-source ledger
2026-02-27 · NCT07437560
2025-03-01 · PMID 40210573 · DOI 10.1016/j.ijom.2025.03.014
2025-01-24
2024-09-20 · PMID 39302005 · DOI 10.1111/1556-4029.15633
2021-02-01 · PMID 33460908 · DOI 10.1016/j.esxm.2020.100298
2020-01-01 · PMID 31953620
2012-11-05 · PMID 23121206 · DOI 10.3109/15563650.2012.740637
2000-10-01 · PMID 11018622 · DOI 10.1016/S0090-4295(00)00680-4
1998-08-01 · PMID 9679884
1996-01-01 · PMID 8637402 · DOI 10.1016/0024-3205(96)00160-9