What is Vyleesi?

What sources report

Vyleesi contains bremelanotide, a synthetic cyclic peptide of seven amino acids with a free acid at one end and an acetylated amino group at the other.² The label describes it as a melanocortin receptor agonist that activates several receptor subtypes.² At treatment doses, binding to MC1R and MC4R matters most.² Nerve cells with MC4R are found in many areas of the central nervous system, but the label states that the mechanism by which Vyleesi improves HSDD is unknown.² The compound is covered in depth in What is PT-141?.

Who it is approved for

The approved use is narrow. HSDD here means low sexual desire that causes marked distress or interpersonal difficulty and is not due to another medical or psychiatric condition, relationship problems, or a medicine or drug.² It must be acquired, meaning it developed after a time without desire problems.² It must also be generalized, meaning it occurs regardless of situation or partner.² The label excludes postmenopausal women, men and use to enhance sexual performance.² Safety and effectiveness have not been established in children or older adults.²

What the trials showed

The label's efficacy and safety data come from two identical 24-week phase 3 trials.² They randomized 1,267 premenopausal women to Vyleesi 1.75 mg as needed (635 women) or placebo (632).²⁹ Participants averaged 39 years old, had been in monogamous relationships for about 12 years and had had HSDD for about 4 years.² The desire score runs from 1.2 to 6.² Average scores rose 0.5 and 0.6 points with Vyleesi versus 0.2 with placebo.² Distress about low desire, scored from 0 to 4, fell 0.7 points versus 0.4.² The number of satisfying sexual events showed no significant difference from placebo.² More women on Vyleesi left the blinded phase early: 40% versus 13% in one study and 39% versus 25% in the other.² Independent reviews of the effect size are summarized in PT-141 benefits and uses.

How it compares with Addyi

Addyi (flibanserin) is also FDA approved for acquired, generalized HSDD in women.¹⁰ It is a 100 mg tablet taken every night at bedtime, while Vyleesi is an injection used only as needed.¹⁰² After a December 2025 label change, Addyi covers women under 65, including postmenopausal women.¹⁰ Its label describes a trial of 902 postmenopausal women under 65, with 447 on Addyi and 455 on placebo.¹⁰ Addyi carries a boxed warning for severe low blood pressure and fainting, including with alcohol taken close in time; Vyleesi has no boxed warning.¹⁰² Addyi acts on serotonin receptors, while Vyleesi acts on melanocortin receptors.¹⁰² Both labels say to stop after 8 weeks if symptoms have not improved.²¹⁰ Neither is approved for men.¹⁰²

Side effects

In the phase 3 trials, the most common side effect was nausea, in 40.0% of Vyleesi users versus 1.3% on placebo.² Next came flushing (20.3% vs 0.3%), injection site reactions (13.2% vs 8.4%), headache (11.3% vs 1.9%) and vomiting (4.8% vs 0.2%).² Most events were mild (31%) or moderate (40%) and short-lived.² Serious adverse reactions occurred in 1.1% of Vyleesi users versus 0.5% on placebo.² Side effects led 18% to stop, versus 2% on placebo, and nausea led 8% to leave the trials.² Full list: PT-141 side effects.

Warnings and precautions

• Contraindications: uncontrolled high blood pressure and known cardiovascular disease are the only two listed.²
• Blood pressure: each dose raises systolic pressure by up to 6 mmHg and diastolic by up to 3 mmHg, peaking 2 to 4 hours after the dose.² Heart rate falls by up to 5 beats per minute, and both usually return to baseline within 12 hours.² Using it more often than prescribed can raise blood pressure further.²
• Daily dosing: in 127 premenopausal women given Vyleesi once daily for 8 days, average daytime systolic pressure rose 1.9 mmHg and diastolic 1.7 mmHg.²
• Skin darkening: patches can appear on the face, gums and breasts.² After 8 daily doses, 38% developed them, and another 14% did after 8 more days.² The label advises considering stopping if it occurs.²
• Other medicines: Vyleesi may slow stomach emptying. The label says to avoid it with oral drugs that need a threshold blood level, such as antibiotics, and with oral naltrexone for alcohol or opioid addiction.²
• Pregnancy and breastfeeding: studies in pregnant dogs suggest possible fetal harm, so the label advises effective contraception and stopping if pregnancy is suspected.² A label update from a completed breastfeeding trial was approved in October 2026 but was not yet public on October 24, 2026.¹¹¹

Dosage information

The label sets one dose: 1.75 mg injected under the skin of the abdomen or thigh, as needed, at least 45 minutes before expected sexual activity.² There is one strength and no titration or escalation step.² The prescriber sets the dose and decides whether Vyleesi suits the patient. The label allows no more than one dose in 24 hours and does not recommend more than 8 doses a month.² It says to stop after 8 weeks if the patient reports no improvement.² Because Vyleesi is used as needed, the label gives no missed-dose instructions.² The label table, the kidney and liver guidance and published study doses are on PT-141 dosage.

How it is used

The Instructions for Use describe a single-dose autoinjector and say not to inject Vyleesi until a healthcare provider has given training.² The steps, in order:

1. Check the autoinjector. Do not use it after the expiration date. The medicine should be clear and free of particles. If the view window is already purple, that autoinjector will not work.²
2. Choose a site. Use the stomach area or the front of the thigh, staying 2 inches away from the belly button.² Avoid skin that is irritated, sore, bruised, red, hard or scarred. Do not inject through clothing, and use a different site each time.²
3. Clean the skin. Wipe the site with an alcohol wipe and let it air dry without fanning or blowing on it.²
4. Activate it. Pulling off the clear cap activates the autoinjector. Use it right away and do not try to recap it.²
5. Inject. Press and hold it firmly against the skin. The first click means the injection has started, and a second click follows in about 2 seconds.² Keep holding for about 5 more seconds.²
6. Confirm the dose. A purple view window with a small part of the gray tip showing means the full dose was given.²
7. Dispose of it. One autoinjector is one dose. Put it in an FDA-cleared sharps disposal container right away, not in household trash.²

Abdomen and thigh injections gave similar drug levels in the blood.² Vyleesi is stored at or below 25°C (77°F), not frozen, protected from light and out of reach of children.² The label lists cartons of 4 and of 2 autoinjectors.² For general background on how prescribed injections under the skin are given, see How subcutaneous injections are given.

Regulatory status

FDA approved Vyleesi (NDA 210557) on June 21, 2019, as a new molecular entity, in a letter to AMAG Pharmaceuticals.¹⁶ It is prescription only, and DailyMed lists its DEA schedule as None.¹² The 2019 label was issued for AMAG and the 2020 label for Palatin Technologies.¹²⁸ As of October 2026, Cosette Pharmaceuticals holds the application and markets the drug.¹²

At approval, FDA required two pregnancy outcome studies, one of them a pregnancy exposure registry, and a trial in breastfeeding women.⁶ In October 2026 FDA approved labeling supplement S-005, based on that breastfeeding trial.¹¹ It updates the label section on specific populations and the patient section on what to know before use.¹¹ As of October 24, 2026, Drugs@FDA said the new label was not available on its site.¹

Drugs@FDA lists one product under the application: the 1.75 mg/0.3 mL autoinjector for use under the skin.¹ No nasal form is part of the approval. Our sources did not confirm the status of bremelanotide on the WADA Prohibited List or any approval outside the United States.