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FDA-approved

PT-141

aka Bremelanotide, Vyleesi

Melanocortin receptor agonist (libido)

Peptide·Facts·ReferencePT-141Melanocortin receptor agonist (…Lot · ref/PT-141 · 2026·05
The vial
P1
The molecule

Half-life

~2 hours; effect duration 4–8 hours

How long it stays active in your body

Dosing

Per use — 45 min before desired effect; max 8 doses/month

How often you take a dose

Route

SubQ

How it goes into the body

Status

FDA

Approved by the FDA for prescription use

Education only. Many compounds discussed are research chemicals not approved for human use in the US. This is not medical advice — consult a licensed physician.

What it is

A synthetic peptide analog of α-MSH that acts centrally on melanocortin-4 receptors in the brain to drive sexual desire. FDA-approved as Vyleesi for premenopausal women with hypoactive sexual desire disorder. Cross-applies off-label in men.

How it works

Activates MC4R in the hypothalamus, triggering dopamine release in the reward pathway. Works centrally on desire — not vascularly like PDE5 inhibitors (Viagra/Cialis). Effect is independent of blood flow.

What the research says

Phase 3 trials in premenopausal women showed significant improvement in desire and satisfaction. Off-label use in men is widespread but lacks dedicated RCT data — informal reports consistently positive.

Sources: FDA Vyleesi label · PubMed: Bremelanotide

Common dosing ranges

Range
1.75 mg SubQ (Vyleesi label); off-label 0.5–2 mg
Frequency
Per use — 45 min before desired effect; max 8 doses/month
Duration
As needed; not daily

Sources: FDA label

Administration

SubQ

Side effects

Common

  • Nausea (~40% of users — most common)
  • Flushing
  • Headache
  • Injection site reactions

Serious / theoretical

  • Transient BP elevation
  • Avoid in uncontrolled hypertension or cardiovascular disease
  • Skin hyperpigmentation with chronic high-dose use

Sources: FDA label

Notes

JD Denham, Froese, and Jay Campbell's library all reference PT-141 for libido. Dr. Jones DC notes FDA approval for women cross-applies in men. Take on empty stomach to minimize nausea.