Libido

PT-141, simplified.

Also called Bremelanotide, Vyleesi

Approved Rx

A prescription peptide for low sexual desire that works on the brain, not blood flow.

Size
7 amino acids (ring-shaped)
How it is taken
Injection as needed
Status
FDA-approved for one use

What is it?

PT-141 acts on melanocortin receptors in the brain, which are involved in desire. That is different from drugs like Viagra, which work on blood flow.

What studies show

What we don’t know yet

Side effects and cautions

Is it legal?

Common questions

What is PT-141?

A prescription peptide for low sexual desire that works on the brain, not blood flow. PT-141 acts on melanocortin receptors in the brain, which are involved in desire. That is different from drugs like Viagra, which work on blood flow.

What does the research say about PT-141?

In two large trials of premenopausal women with low desire, it modestly improved desire and reduced distress compared with placebo.

Is PT-141 FDA approved?

FDA-approved for premenopausal women with low sexual desire. Other uses are off-label.

What are the side effects of PT-141?

Nausea is common, affecting about 4 in 10 people in trials. It can briefly raise blood pressure. Repeated use can darken patches of skin.

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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-09-26.