Compare

Melanotan II vs TB-500 Fragment

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.

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

TB-500 Fragment

26 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 3% · Mixed 97% · Unfavorable overall 0%

Most reported benefits

Benefits users selected when logging a favorable or mixed check-in.

Recovery
176

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.

Injection site irritation
171

Self-reported dose per injection

Median bucket: 2+ mg · Most common: 2+ mg

Reports span 1 to ≥ 2 mg (open-ended top bucket)

1–2 mg
59
2+ mg
117

Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.

How repeat users are trending

Among repeat reporters, 79% said they felt similar to their last entry, 21% more positive, and 0% more negative.

Overall, repeat reporters leaned more positive than their previous entry.

Median gap between entries: 188 days · Based on 24 repeat reporters

Sources (6)

Published sources linked on the Melanotan II and TB-500 Fragment wiki pages.

  1. 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

    Source
    Wiki study page →
  2. PubMed

    Melanotan II injection resulting in systemic toxicity and rhabdomyolysis

    Nelson ME, Bryant SM, Aks SE. Clinical toxicology (Philadelphia, Pa.). 2012

    Source
    Wiki study page →
  3. PubMed

    Thymosin beta4: a multi-functional regenerative peptide (review)

    Goldstein AL, Kleinman HK. Ann N Y Acad Sci. 2012

    Source
    Wiki study page →
  4. PubMed

    Thymosin beta 4 and wound healing: a multifunctional peptide

    Goldstein AL, Kleinman HK. Expert Opin Biol Ther. 2010

    Source
    Wiki study page →
  5. PubMed

    Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance

    Mendias CL, Awan TM. Sports medicine (Auckland, N.Z.). 2026

    Source
    Wiki study page →