PT-141 is the research name for bremelanotide, a synthetic cyclic heptapeptide that activates melanocortin MC3R and MC4R receptors in the brain.

What is the FDA-approved PT-141 dose?

The FDA-approved Vyleesi label lists 1.75 mg subcutaneous, given at least 45 minutes before sexual activity.

Is PT-141 approved for men?

No, the FDA approval is specifically for premenopausal women with HSDD.

Is PT-141 nasal spray FDA-approved?

No, the FDA-approved bremelanotide product is an injection (Vyleesi).

How long does PT-141 take to work?

The Vyleesi label and Phase 3 trial design use a ≥45-minute interval before sexual activity.

What are the most common side effects?

Nausea is the most common adverse event, reported in about 40% of users.

Who should avoid PT-141?

PT-141 should not be used by people with uncontrolled hypertension or known cardiovascular disease.

Can PT-141 be combined with sildenafil or tadalafil?

There is no formal clinical evidence combining PT-141 with PDE5 inhibitors.

Peptide

PT-141

PT-141 (bremelanotide) is a melanocortin receptor agonist studied in research applications related to neural signaling pathways.

Researched for

Recovery

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The best origin story in the whole series: it started life as a tanning drug, and the side effect became the product.

Not yet audited

We have not published an audit on PT-141. Everything below is reference material, not our own reading of the literature, treat it as a starting point for questions, not as a grade.

How it is thought to work

PT-141 (bremelanotide) is a synthetic cyclic peptide that activates two melanocortin receptors in the brain, MC3R and MC4R, working through the central nervous system rather than by changing blood flow. [Source: Peptide Dosing Protocols]

PT-141 works by activating two receptors in the brain (MC3R and MC4R) to increase sexual desire through the central nervous system, not by changing blood flow like Viagra or Cialis.

Reported side effects

The most common side effects are nausea (in about 40% of users), flushing, headache, and injection site reactions, most of which are mild, decrease over time, and rarely cause people to stop using it.

What sources report

Reference, not a recommendation

These are figures published elsewhere, reproduced with their source. Peppersite does not recommend an amount for PT-141 or for anything else, and nothing below has been checked against the study it came from.

Amount	Frequency	Route	Reported by
1.75 mg	not stated	subcutaneous or oral	Peptide Protocol Wiki What it saysHide (secondary reference; provider confirmation required).
Standard: 1.75 mg	1 dose per 24 hours8 doses per month	Subcutaneous (abdomen or thigh)	Peptide Dosing Protocols What it saysHide (secondary reference; provider confirmation required). The standard dose of PT-141 is 1.75 mg subcutaneous at least 45 minutes before sexual activity.
Injection referenced at 0.5-2 mg per dose with onset in 1-4 hours, peak at 6-12 hours, duration 24-72 hours. Nasal spray referenced at 2-4 sprays per nostril, onset 30-60 minutes, duration 6-12 hours. Start low; side effects are dose-dependent (nausea most common).	As needed · On-demand, 1-4 hours before desired effect (injection)	subcutaneous or nasal	Peptide Therapy Reference Text, internal KB v4 What it saysHide (Aug 2026), secondary reference; provider confirmation required.

1.75 mg

Frequency: not stated
Route: subcutaneous or oral
Reported by: Peptide Protocol Wiki
What it saysHide
(secondary reference; provider confirmation required).

Standard: 1.75 mg

Frequency: 1 dose per 24 hours8 doses per month
Route: Subcutaneous (abdomen or thigh)
Reported by: Peptide Dosing Protocols
What it saysHide
(secondary reference; provider confirmation required). The standard dose of PT-141 is 1.75 mg subcutaneous at least 45 minutes before sexual activity.

Injection referenced at 0.5-2 mg per dose with onset in 1-4 hours, peak at 6-12 hours, duration 24-72 hours. Nasal spray referenced at 2-4 sprays per nostril, onset 30-60 minutes, duration 6-12 hours. Start low; side effects are dose-dependent (nausea most common).

Reconstitution, as reported

reconstitution math, route considerations, and side effects for this bremelanotide peptide.

Sources

01Mayo Clinic / Merative Micromedex Bremelanotide (subcutaneous route) — Description and Dosing. Mayo Clinic Drugs & Supplements (2026)

02Kingsberg SA, Clayton AH, Portman D, et al. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials. Obstetrics & Gynecology (2019)

03Simon JA, Kingsberg SA, Portman D, et al. Long-Term Safety and Efficacy of Bremelanotide for Hypoactive Sexual Desire Disorder. Obstetrics & Gynecology (2019)

04Clayton AH, Althof SE, Kingsberg S, et al. Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial. Women's Health (London) (2016)

05Diamond LE, Earle DC, Rosen RC, Willett MS, Molinoff PB. Double-blind, placebo-controlled evaluation of the safety, pharmacokinetic properties and pharmacodynamic effects of intranasal PT-141, a melanocortin receptor agonist, in healthy males and patients with mild-to-moderate erectile dysfunction. International Journal of Impotence Research (2006)

06Safarinejad MR. Evaluation of the safety and efficacy of bremelanotide, a melanocortin receptor agonist, in female subjects with arousal disorder: a double-blind placebo-controlled, fixed dose, randomized study. Journal of Sexual Medicine (2008)

07Pfaus JG, Shadiack A, Van Soest T, Tse M, Molinoff P. Selective facilitation of sexual solicitation in the female rat by a melanocortin receptor agonist. Proceedings of the National Academy of Sciences USA (2004)

08Simon JA, Kingsberg SA, Portman D, et al. Prespecified and Integrated Subgroup Analyses from the RECONNECT Phase 3 Studies of Bremelanotide. Journal of Women's Health (2022)

09Pfaus J, Giuliano F, Gelez H. Bremelanotide: An overview of preclinical CNS effects on female sexual function. Journal of Sexual Medicine (2007)

10Loti Labs (Editorial). PT-141 (Bremelanotide): Melanocortin Receptor Agonist Research Guide. Loti Labs Resources (2026)