PubMed
Melanotan II and its molecular mechanisms
Dorr RT, Dawson BV, Hadley ME, et al. Life Sci. 2009
Compare
Melanotan II vs Retatrutide
Side-by-side observational reports from PeptIQ users. This compares self-reported patterns — not clinical head-to-head trials.
Last reviewed . By the PeptIQ team.
Observational reporting only — not medical advice. Does not recommend doses, protocols, or treatments.
Melanotan II
46 community reports
Overall experience
From check-in ratings — separate from side effects logged below. Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Favorable 97% · Mixed 3% · Unfavorable overall 0%
Most reported benefits
Benefits users selected when logging a favorable or mixed check-in.
Libido
142
Mood
141
Appetite
73
Most logged side effects
Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Fatigue
2
Nausea
2
Self-reported dose per injection
Median bucket: 0.4–0.6 mg · Most common: 0.2–0.4 mg
Reports span 0.01–2 mg
0.01–0.025 mg
1
0.05–0.1 mg
1
0.1–0.2 mg
7
0.2–0.4 mg
49
0.4–0.6 mg
23
0.6–1 mg
33
1–2 mg
28
Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.
Commonly stacked with
How repeat users are trending
Among repeat reporters, 94% said they felt similar to their last entry, 6% more positive, and 0% more negative.
Overall, repeat reporters leaned more positive than their previous entry.
Median gap between entries: 50 days · Based on 32 repeat reporters
Retatrutide
125 community reports
Overall experience
From check-in ratings — separate from side effects logged below. Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Favorable 99% · Mixed 1% · Unfavorable overall 0%
Most reported benefits
Benefits users selected when logging a favorable or mixed check-in.
Appetite
222
Most logged side effects
Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Nausea
3
Self-reported dose per injection
Median bucket: 2–3 mg · Most common: 1–2 mg
Reports span 0 to ≥ 5 mg (open-ended top bucket)
0–0.01 mg
5
0.1–0.2 mg
3
0.2–0.4 mg
6
0.4–0.6 mg
10
0.6–1 mg
5
1–2 mg
80
2–3 mg
35
3–5 mg
17
5+ mg
61
Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.
Commonly stacked with
How repeat users are trending
Among repeat reporters, 100% said they felt similar to their last entry, 0% more positive, and 0% more negative.
Overall, repeat reporters leaned similar or mixed compared to their previous entry.
Median gap between entries: 51 days · Based on 45 repeat reporters
Sources (9)
Published sources linked on the Melanotan II and Retatrutide wiki pages.
- Wiki study page →Source
- Wiki study page →Source
PubMed
LC-HRMS characterization of the skin pigmentation and sexual enhancers melanotan II and bremelanotide sold on the black market of performance and image enhancing drugs
Mestria S, Odoardi S, Frison G, et al. Drug testing and analysis. 2021
- Wiki study page →Source
PubMed
Melanotan II injection resulting in systemic toxicity and rhabdomyolysis
Nelson ME, Bryant SM, Aks SE. Clinical toxicology (Philadelphia, Pa.). 2012
- Wiki study page →Source
PubMed
Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes
Rosenstock J, Frias J, Jastreboff AM, et al. Lancet. 2023
- Wiki study page →Source
PubMed
Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial
Jastreboff AM, Kaplan LM, Frias JP, et al. N Engl J Med. 2023
- Wiki study page →Source
ClinicalTrials.gov
Retatrutide obesity studies on ClinicalTrials.gov
ClinicalTrials.gov. Clinical trial registry. 2024
- Wiki study page →Source
ClinicalTrials.gov
Retatrutide studies on ClinicalTrials.gov
ClinicalTrials.gov. Clinical trial registry. 2024
- Wiki study page →Source
PubMed
Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial
Jastreboff AM, Kaplan LM, Frías JP, et al. The New England journal of medicine. 2023
- Wiki study page →Source
PubMed
Retatrutide-A Game Changer in Obesity Pharmacotherapy
Katsi V, Koutsopoulos G, Fragoulis C, et al. Biomolecules. 2025