PT-141
Libido and arousal peptide
Also known as Bremelanotide, Vyleesi, the libido peptide
- Evidence grade
- AApproved, phase 3 dataScale
- Half-life
- About 2.7 hours
- Schedule
- As needed before activity, subcutaneous
- Maintenance amount
- 1.75 mg
- Vial sizes sold
- 10 mg
Where a value is not established in people, this table says so rather than filling the box.
PT-141, known as bremelanotide, is a melanocortin receptor agonist derived from an earlier tanning peptide. It is studied for low sexual desire and is approved as Vyleesi for premenopausal women with hypoactive sexual desire disorder.
It activates melanocortin receptors, mainly MC4R, in the central nervous system rather than acting on blood vessels. This central action influences brain pathways tied to sexual desire and arousal. Because it works through the brain, its effect differs from erection drugs that target blood flow. This mechanism is backed by human phase 3 trials.
Human phase 3 trial data; approved as Vyleesi for premenopausal hypoactive sexual desire disorder.
- Studied for increasing sexual desire in premenopausal women with low libido
- Researched for improving arousal through a central brain pathway
- Works independently of the blood-flow mechanism of erection drugs
- Dosed only as needed rather than daily
- Nausea, sometimes significant, especially with the first doses
- Flushing and headache
- Temporary rise in blood pressure and drop in heart rate
- Darkening of skin or gums with frequent use
A summary of the research, not medical advice. Individual benefits and risks vary, and for some of these compounds the human evidence is still early.
Unlike most peptides on this site, PT-141 is generally reported as an acute, per-dose compound rather than one with a cumulative weekly buildup. Onset is commonly reported within 30 to 60 minutes, lasting several hours, with nausea and flushing as the most reported side effects.
Read the full timeline →Drawn from published trial data and how the research community commonly describes this stretch. Not a fixed schedule and not medical advice.
As needed before activity, subcutaneous. For research reference only, not medical advice.
| Phase | Amount |
|---|---|
| As needed | 1.75 mg, up to 45 min before |
No more than one dose per 24 hours or eight per month, per the approved label.
A rough shopping estimate at the maintenance amount. Your real needs shift with your dose and titration.
| Item | 12-week plan | 18-week plan | 24-week plan |
|---|---|---|---|
| Peptide vials (10 mg) | 3 | 4 | 5 |
| Insulin syringes (U-100) | 12 | 18 | 24 |
| Bacteriostatic water (10 mL) | 1 | 1 | 1 |
| Alcohol swabs (100-count box) | 1 | 1 | 1 |
Lyophilized: Keep the sealed powder cold and dark, near -20 °C, dry and out of light.
Reconstituted: Refrigerate the mixed vial at 2 to 8 °C, use within a few weeks and avoid freeze and thaw.
Let a cold vial reach room temperature before you open it, so it takes on less condensation.
How strong is the evidence for PT-141?
We grade it A on a four-point scale. Phase 3 data. Approved as Vyleesi.
What is the half-life of PT-141?
About 2.7 hours. That is the figure the reported dosing frequency follows from.
What amount of PT-141 is used in the research?
As needed: 1.75 mg, up to 45 min before. No more than one dose per 24 hours or eight per month, per the approved label.
How is PT-141 stored once reconstituted?
Refrigerate the mixed vial at 2 to 8 °C, use within a few weeks and avoid freeze and thaw.
- Kingsberg SA, et al. Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials. Obstet Gynecol. 2019;134:899-908.
- Clayton AH, et al. Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial. Womens Health (Lond). 2016;12:325-337.