Skip to content
The Peptide Effect
Dosage Guide

PT-141 (Bremelanotide) Dosage Guide & Protocol

Educational reference for PT-141 (bremelanotide) dosage protocols, administration guidelines, and safety information as discussed in published clinical research.

View PT-141 profile →

Medical Disclaimer

This guide is for educational and informational purposes only. It is not medical advice. Dosages described reflect ranges discussed in published research and clinical practice literature — they are not recommendations. Always consult a licensed healthcare provider before using any peptide. Legality and availability vary by jurisdiction.

Overview

PT-141, also known as bremelanotide, is a synthetic melanocortin receptor agonist that acts on MC3R and MC4R receptors in the central nervous system to modulate sexual arousal and desire. It was approved by the FDA in 2019 under the brand name Vyleesi for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women. PT-141 is structurally derived from the tanning peptide Melanotan II but was specifically developed for its effects on sexual function rather than melanogenesis. Unlike PDE5 inhibitors such as sildenafil, PT-141 works centrally through melanocortin pathways rather than through peripheral vasodilation, which has generated research interest for both male and female sexual dysfunction. The dosage information below is compiled from published clinical trials and FDA labeling for educational reference only.

Dosing Protocols

FDA-Approved On-Demand Protocol (Vyleesi)

Route: Subcutaneous (abdomen)
Dose: 1.75 mg
Frequency: On-demand, at least 45 minutes before anticipated sexual activity
Duration: As needed — not intended for daily use

This is the FDA-approved dose for premenopausal women with HSDD. Do not administer more than one dose within a 24-hour period. Do not use more than 8 doses per month per FDA labeling. Auto-injector device (Vyleesi) delivers a pre-measured 1.75 mg dose.

Lower Starting Dose (Tolerance Assessment)

Route: Subcutaneous
Dose: 0.5–1 mg
Frequency: On-demand, 45–60 minutes before activity
Duration: As needed

Discussed in community protocols for individuals new to PT-141 who want to assess tolerance before using the full dose. Nausea is the most common side effect and tends to be dose-dependent, so starting lower may help identify individual sensitivity.

Research / Male Protocol

Route: Subcutaneous
Dose: 1–2 mg
Frequency: On-demand
Duration: As needed — limit to no more than 2 uses per week

Early clinical studies by Diamond et al. (2005) explored PT-141 in men with erectile dysfunction at doses of 1–10 mg. The 2–4 mg range was reported as most effective in those studies. Community protocols typically discuss 1–2 mg for male use. PT-141 is not FDA-approved for use in men.

Reconstitution & Storage

Vial sizes10 mg lyophilized powder per vial (research peptide format)
Recommended water volume2 mL bacteriostatic water (BAC water), yielding 5 mg/mL
StorageStore unreconstituted vials at 2–8 °C (36–46 °F). The FDA-approved Vyleesi auto-injector is stored at room temperature (20–25 °C).
Stability once reconstitutedReconstituted research peptide solution is generally stable for up to 30 days when refrigerated. The Vyleesi auto-injector does not require reconstitution and has a manufacturer-determined shelf life.

Use our reconstitution calculator to determine exact syringe units for your dose.

Cycle Guidance

PT-141 is intended for on-demand use rather than continuous daily dosing. The FDA labeling recommends no more than 8 doses per month. Tachyphylaxis (reduced response with repeated use) has been discussed in research, so allowing adequate time between doses may help maintain efficacy. There is no established cycling protocol for PT-141 in the traditional sense — it is used situationally rather than in fixed cycles.

Stacking Considerations

  • PT-141 works through a different mechanism (melanocortin receptors) than PDE5 inhibitors (sildenafil, tadalafil), and their combination has been discussed in research contexts, though this is not FDA-approved.
  • Not typically combined with Melanotan II, as both act on melanocortin receptors and concurrent use could increase the risk of side effects including nausea and blood pressure changes.
  • Oxytocin nasal spray has been discussed alongside PT-141 in some community protocols for sexual wellness, though clinical evidence for this combination is lacking.
  • No known interactions with common supplements, but caution is advised when combining with antihypertensive medications due to potential additive blood pressure effects.

Potential Side Effects

  • Nausea — the most common side effect, reported in approximately 40% of participants in clinical trials. Usually mild to moderate and transient.
  • Flushing (warmth and redness of the skin, particularly face and chest)
  • Headache
  • Injection site reactions (bruising, pain, redness)
  • Transient increase in blood pressure — FDA labeling notes an average increase of approximately 2–3 mmHg systolic
  • Skin hyperpigmentation with repeated use (darkening of gums, face, or breasts) — related to melanocortin activity
  • Fatigue or drowsiness
  • Nasal congestion (less common)

Contraindications & Cautions

  • Uncontrolled hypertension or significant cardiovascular disease — PT-141 can transiently increase blood pressure
  • Known hypersensitivity to bremelanotide or any inactive ingredient in the formulation
  • Concurrent use with naltrexone — co-administration significantly reduces the efficacy of both drugs (FDA contraindication)
  • Pregnancy — FDA labeling advises against use during pregnancy
  • Hepatic impairment — bremelanotide is metabolized by the liver and exposure may be increased
  • History of melanoma or predisposition to melanotic conditions — theoretical concern due to melanocortin receptor activity

Related

PT-141 Profilesexual healthselank dosage

References

  1. An evaluation of the erectile response to bremelanotide (PT-141), a melanocortin receptor agonist, in men with erectile dysfunction (2005) — PubMed
  2. Bremelanotide for hypoactive sexual desire disorder: efficacy and safety from a phase 3 RECONNECT study (2019) — PubMed
  3. Melanocortin receptor agonists for the treatment of sexual dysfunction (2006) — PubMed
  4. Vyleesi (bremelanotide) prescribing information (2019)

Frequently Asked Questions

How quickly does PT-141 work?
The FDA labeling for Vyleesi recommends administration at least 45 minutes before anticipated sexual activity. In clinical trials, onset of effect was typically reported between 30–60 minutes after injection. The effects can last several hours, with some studies reporting residual effects for up to 12–24 hours. Individual response times vary.
What is the difference between PT-141 and Viagra (sildenafil)?
PT-141 and PDE5 inhibitors like sildenafil work through entirely different mechanisms. Sildenafil acts peripherally by increasing blood flow to genital tissue through nitric oxide and cGMP pathways. PT-141 acts centrally in the brain through melanocortin receptors (MC3R/MC4R) to modulate sexual desire and arousal. This distinction means PT-141 addresses desire and arousal at a neurological level, while PDE5 inhibitors primarily address the vascular component of erectile function.
Can PT-141 be used by men?
The FDA approved Vyleesi specifically for premenopausal women with HSDD. However, early clinical trials by Diamond et al. (2005) studied PT-141 in men with erectile dysfunction and reported positive results at doses of 2–4 mg. PT-141 is not FDA-approved for male use, and the research in male populations is more limited than in female populations. Community protocols discussing male use are based on these earlier studies.
Why does PT-141 cause nausea?
Nausea is likely related to PT-141's activation of melanocortin receptors in the brainstem, particularly in the area postrema, which is involved in the vomiting reflex. Nausea was the most frequently reported side effect in clinical trials (approximately 40% of participants). It is typically dose-dependent and transient, resolving within a few hours. Starting with a lower dose may help manage this side effect.
How often can PT-141 be used safely?
The FDA labeling for Vyleesi limits use to no more than one dose per 24-hour period and no more than 8 doses per calendar month. These limits were established based on clinical trial data and are intended to reduce the risk of tachyphylaxis (diminishing response) and to manage side effects such as skin hyperpigmentation that may occur with frequent use.
Does PT-141 cause skin darkening?
Yes, skin hyperpigmentation is a recognized side effect listed in the FDA labeling. PT-141 activates melanocortin-1 receptors (MC1R), which stimulate melanin production. Darkening of the gums, face, and breasts has been reported. The risk appears to increase with more frequent use, which is one reason the FDA recommends limiting doses to no more than 8 per month.