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PT-141

Boosts sex drive and arousal

Bremelanotide (Vyleesi)

Match every finding to its exact substance, formulation, route and study population. A related molecule or approved medicine does not validate a catalog vial.

Human / product-specific records
Explore the evidenceWhy people take it
Compare this compoundRead original sources Community reports
AcNleDHfRWKOH
Schematic illustration · View structure evidence

Ring closed by a lactam bridge, a bond between two side chains

Color key
NonpolarAromaticPositive chargeNegative chargePolar Copper ion D-form or non-natural

At a glance

Why people take it. And what backs it up.

  1. Boost sex drive

    Approved for women with low desire

    Approved as Vyleesi for women before menopause whose low sex drive distresses them; injected at least 45 minutes before sex, it modestly raised desire.

    Sources (4)

  2. Get stronger erections

    Small studies; not approved for men

    Many men inject it or use a nasal spray before sex for stronger arousal and erections, sometimes alongside Viagra or Cialis.

    Sources (4)

  3. Restore libido on antidepressants

    People report it, not studied

    People whose antidepressants dulled their sex drive try it, sometimes at high doses or with Cialis, with mixed results.

    Sources (2)

  4. Spice up sex

    People report it, not studied

    Couples without sexual problems take it before sex for stronger desire and arousal; the approved drug’s label says it is not for enhancing performance.

    Sources (3)

Evidence briefing

Sources checked

What the sources support.

PT-141 is bremelanotide. FDA approval is for Vyleesi, a specific 1.75 mg subcutaneous autoinjector used as needed for acquired, generalized HSDD in premenopausal women. FDA labeling explicitly excludes men, postmenopausal women and sexual-performance enhancement. The approval does not cover online PT-141 vials or establish an approved treatment for erectile dysfunction in men.

Keep in mind

Trials in men or earlier bremelanotide development do not broaden the current FDA indication, and seller vials are not the labeled autoinjector product.

Identity and research status reviewRead the original sources

The research. What’s been studied.

TapClick a dotted word to see what it means.

  • Human evidence

    Desire in the approved population

    Vyleesi increased desire in premenopausal women with acquired, generalized HSDD in trials; the benefit is modest and applies to the labeled population.

  • Human evidence

    Reduced distress

    The same trials found reduced distress associated with low desire in the labeled population.

  • Early human studies

    Not an approved ED treatment

    Earlier studies examined erectile effects in men, but bremelanotide is not FDA-approved to treat erectile dysfunction or for men.

  • Human evidence

    As-needed labeled product

    Vyleesi is used as needed before anticipated sexual activity under its FDA label; this does not validate seller PT-141 vials.

What do these labels mean?
  • Human evidence: approved-drug data or larger human studies, within the populations and uses studied.
  • Early human studies: small, preliminary or limited human studies.
  • Animal & lab studies: animal or laboratory findings that do not establish effects in people.
  • Unverified: a proposed use or claim without verified supporting clinical evidence.
How each claim was reviewed (4)

Reported effects and evidence.

A citation may support, qualify or correct a claim. Read the study scope; a laboratory result is not an established benefit in people. Each review covers a claim as it was first collected; the tiles above show the collection’s current wording.

  1. FDA-approved indication; human phase 3 trials

    Review of “More sexual desire”

    Vyleesi trials found modest desire-score improvement in premenopausal women with acquired, generalized HSDD meeting trial criteria.

    Limitations and applicability. Specify acquired generalized HSDD and exclusions; does not imply general enhancement, men or postmenopausal indication.

    Original collected claim and review history

    Original title: More sexual desire

    Increased desire in premenopausal women with low sexual desire in two Phase 3 trials.

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record pt-141:benefit:1 · Annotated 2026-10-01 · Review method

  2. Human phase 3 patient-reported outcome

    Review of “Less distress”

    The same trials found improvement in distress related to low sexual desire.

    Limitations and applicability. Distress is a separate endpoint; greater desire/distress effects do not imply more satisfying sexual events.

    Original collected claim and review history

    Original title: Less distress

    Reduced distress about low desire in the same trials.

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record pt-141:benefit:2 · Annotated 2026-10-01 · Review method

  3. Earlier human studies; research-integrity warning

    Review of “Erections in men”

    Earlier male ED studies reported responses, but the sildenafil-nonresponder trial carries an Expression of Concern and should be presented cautiously.

    Limitations and applicability. The sildenafil-failure RCT has a 2023 Expression of Concern. Preserve historical report with warning; do not treat it as settled evidence.

    Original collected claim and review history

    Original title: Erections in men

    Produced erections in earlier trials, including in some men who didn’t respond to Viagra-type drugs.

    Original label: early. Preserved for traceability; the reviewed wording above qualifies this record.

    Record pt-141:benefit:3 · Annotated 2026-10-01 · Review method

  4. Approved-product administration feature

    Review of “Taken as needed”

    The approved product is intended for as-needed use within its specific indication and label restrictions.

    Limitations and applicability. A schedule is not an efficacy benefit; applies only within approved indication and label limits.

    Original collected claim and review history

    Original title: Taken as needed

    Used before sexual activity, not daily.

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record pt-141:benefit:4 · Annotated 2026-10-01 · Review method

The research in detail

Evidence category

FDA-approved (US)

Two Phase 3 trials supported the narrow FDA indication for premenopausal women with acquired, generalized HSDD. Earlier studies in men do not establish an approved erectile-dysfunction treatment. The Vyleesi label excludes use in men, postmenopausal women and for enhancing sexual performance.

Evidence is assessed claim by claim above. Regulatory approval, study design, findings and relevance are separate questions; there is no single evidence score.

Risks and unknowns. What to know first.

Collected cautions follow. These are not an exhaustive or independently validated safety assessment; claim references do not automatically support every caution.

  • Nausea is common (about 40% in trials), along with flushing, headache and a temporary rise in blood pressure.
  • Repeated use can darken skin and gums.

What people report

Show all 5 cautionsShow fewer cautions

Read this first: what “research use only” means

Published dosing records. What the approved label says.

Historical label and trial records for the named product, route, population and indication. These records are not a personal schedule or a validated regimen for a catalog vial. Source attribution does not establish applicability.

Vyleesi

Premenopausal women with acquired, generalized low sexual desire (hypoactive sexual desire disorder) that causes distress and is not due to another condition, relationship problems or a medicine

As neededApproved label

Source: Vyleesi prescribing information (FDA, revised 03/2024)

Each use
1.75 mg
How
Injection under the skin of the belly or thigh, with a prefilled autoinjector
How often
As needed, at least 45 minutes before expected sexual activity
How long
As needed; stopped after 8 weeks if there is no improvement

Limit. No more than 1 dose in 24 hours, and no more than 8 doses a month.

  • The label says to stop Vyleesi after 8 weeks if the patient reports no improvement.
  • How long each dose works is unknown. The label lets patients choose the timing based on how long the effect lasts for them and on side effects such as nausea.
  • It is not approved for postmenopausal women or for men, or to enhance sexual performance.

These are the label’s doses for the approved medicine, started and adjusted by a prescriber. A research vial is not that medicine: no regulator has checked what’s in it, or how much.

Community protocols. Reported online. Not clinically validated.

Community reports Collection date: 30 Sep 2026

Off-label PT-141 is mostly injected under the skin as needed, 0.5–2 mg a few hours before sex, often after a smaller test dose and with an antihistamine or anti-nausea pill beforehand.

More about this

Much of the forum use is by men, which is off-label. Telehealth clinics also sell compounded nasal sprays (about 1–2 mg per use), and a few users push to 2.5–3.5 mg.

Not testedFrequently encountered in reviewed sources

As-needed injection before sex

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
0.5–2 mg (first dose often 0.5–1 mg)
How often
As needed; most report once or twice a week
Route
Injection under the skin (belly or thigh)
Timing
From about 45 minutes to several hours before sex; users report effects lasting from hours up to a day or more
How long
Used on and off for months
Ramp
Test dose first (0.25–1 mg), then 1–2 mg if tolerated
Mixing
10 mg vial + 2 mL bacteriostatic water, so 500 mcg = 10 units (some use 1 or 3 mL)
  • Many take an antihistamine (cetirizine or diphenhydramine) or an anti-nausea drug (ondansetron, meclizine or hyoscine) 20–30 minutes before.
  • Some men combine it with sildenafil or tadalafil.
Sources (4)

Not testedCommon

Nasal spray

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
Clinic spray: 1 mg per spray, up to 2 mg per use. Grey-market sprays vary widely (one reported 150 mcg per spray).
How often
As needed; one clinic allows no more than once in 24 hours and 3 times a week
Route
Nasal
Timing
45–60 minutes before sex
Ramp
One spray, wait 10–20 minutes, then a second spray if tolerated
  • Several forum users found the spray weaker or less reliable than injections.
Sources (4)
Show all 4 protocolsShow fewer protocols

Not testedSometimes seen

Higher dose for non-responders

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
2.5–3.5 mg
How often
As needed, at least 24 hours apart
Route
Injection under the skin
Ramp
Stepping up by about 0.5–1 mg per attempt
  • Mostly people with sexual problems caused by antidepressants, or people who felt nothing at lower doses.
Sources (2)

Not testedFringe

Very low dose

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
0.1–0.2 mg
How often
As needed
Route
Injection under the skin
  • Seen as a first test dose and in at least one doctor’s prescription (10 units of a 2 mg/mL solution).
Sources (2)

Where the numbers come from

Injection doses cluster around the approved Vyleesi dose (1.75 mg), which some users copy directly, scaled down for tolerance. Compounded nasal sprays echo earlier nasal PT-141 trials and are sold by telehealth clinics. Men’s use is off-label and forum-driven.

Home-made sprays and serums

Home-made nasal spray. Community recipes. Not tested.

Original source recordsHide

PT-141 (bremelanotide) was first developed as a nasal spray and tested at 7.5–20 mg per dose; the maker later moved to injection, and later papers say the nasal route gave widely varying absorption and a higher risk of side effects such as raised blood pressure. Today people use clinic or vendor sprays, or mix a 10 mg vial into 5–10 mL of saline (one guide suggests 200–400 mcg a dose); many say it works poorly by nose.

Best evidence: Clinical trials of intranasal PT-141 by Palatin (2004–2006; 7.5, 10 and 20 mg doses) and a 2008 trial of a 10 mg intranasal spray (now under an expression of concern). The approved product (Vyleesi) is an injection. Home sprays: community only.

Collected strength records

Not testedNasal spraySometimes seen

10 mg vial in 5 mL saline: 200 mcg per 0.1 mL spray

Original source-specific report. Collection checked 30 Sep 2026; presentation annotated 2026-10-01. Source date and reporter identity are not separately verified. Exact form and route are limited to the source’s description.

Batch: 5 mL

Ingredients and methodHide the recipe

Ingredients

IngredientAmountRole
PT-14110 mgActive
Saline5 mLLiquid
How it’s used
Start at 200–250 mcg; most find 250–400 mcg; maximum 1 mg (poster’s advice).
Per dose
200 mcg per 0.1 mL spray (stated).
Preservative
None.
Sources (2)

Not testedNasal spraySometimes seen

10 mg vial with 4 mL saline, topped up to 10 mL

Original source-specific report. Collection checked 30 Sep 2026; presentation annotated 2026-10-01. Source date and reporter identity are not separately verified. Exact form and route are limited to the source’s description.

Batch: 10 mL

Ingredients and methodHide the recipe

Ingredients

IngredientAmountRole
PT-14110 mgActive
Saline4 mL in the vial + 6 mL in the bottleLiquid
How it’s used
6 sprays in one evening (2, then 4 at night); effect came 24 hours later, per the poster.
Per dose
Not stated (spray volume not given).
Preservative
None.
Sources (2)

Not testedNasal spraySometimes seen

Doctor-prescribed or vendor ready-made sprays

Original source-specific report. Collection checked 30 Sep 2026; presentation annotated 2026-10-01. Source date and reporter identity are not separately verified. Exact form and route are limited to the source’s description.

Ingredients and methodHide the recipe

Ingredients

IngredientAmountRole
PT-14110 mg per bottle (vendor label)Active
How it’s used
Doctor advised 1–2 sprays to start; the user took 3 per nostril.
Per dose
Vendor label: 100 mcg per spray. The prescribed spray: 6 sprays ≈ 1.25 mg, per the user.
Sources (3)

Not testedNasal sprayFringe

Clinical-trial intranasal doses (reference, not a home recipe)

Original source-specific report. Collection checked 30 Sep 2026; presentation annotated 2026-10-01. Source date and reporter identity are not separately verified. Exact form and route are limited to the source’s description.

Ingredients and methodHide the recipe

Ingredients

IngredientAmountRole
Bremelanotide (PT-141)7.5 mg, 10 mg or 20 mg single dosesActive
How it’s used
Single doses before sexual activity (10 mg 45 minutes to 2 hours before, in the 2008 trial).
  • The trial formulations were not published in the abstracts.
Sources (4)

How the method was put together, step by step with its sources

Editorial synthesis and reported strength comparison

This synthesized method combines source records. It has not been validated for preparation, sterility, compatibility, absorption or storage. Select a reported strength to inspect the arithmetic; no strength is selected for you.

Strength per spray
What people report
Research notes

Doses and timing vary widely because effects are unpredictable: some users feel nothing at 2.5 mg while others get long-lasting erections at 1 mg. Some forum posts are vendor promotions (discount codes). Frequent dosing is common in forums, although the trial data link repeated daily dosing to skin darkening.

Nasal spray

The 2008 10 mg intranasal trial carries a 2023 expression of concern. The Palatin trials were run by the maker. The vendor label said ‘100 mg per spray’, which the buyer corrected to 100 mcg. The trial doses (7.5–20 mg) are far above the 200–400 mcg users aim for; users claim nasal absorption of ‘10–20%’, unsourced.

Measurement basics and calculator

Explore vial arithmetic

What it is. In plain English.

Bremelanotide (PT-141) is the active ingredient in Vyleesi, FDA-approved for a specific HSDD indication in premenopausal women.

Bremelanotide (PT-141) is a synthetic . FDA approval is for Vyleesi, a specific subcutaneous autoinjector for acquired, generalized HSDD in premenopausal women. It is not approved for men, postmenopausal women or sexual-performance enhancement; seller vials are not the approved product.

It activates melanocortin receptors (mainly MC4R) in brain areas tied to sexual motivation. That’s different from Viagra-type drugs, which increase blood flow.

Reviewed 2026-10-01.

Structure. What it really looks like.

Experimental

Cryo-EM structure of PT-141 (coral) bound to the human melanocortin-4 receptor (gray).

PT-141 (bremelanotide, coral) bound to the human melanocortin-4 receptor (gray). All seven amino acids are resolved. Also part of the experiment, but not drawn: a G protein and an antibody fragment.

Missing parts

  • The acetyl cap at the start of the peptide isn’t in the model.
  • The ring that closes the peptide is drawn from the positions of its atoms: the entry’s file doesn’t list that bond.
  • A calcium ion that touches the peptide and the receptor in the experiment isn’t drawn.

7F55, Zhang et al., 2021. Rendered with Mol* (Sehnal et al., 2021) from RCSB PDB data (Berman et al., 2000).

Specs. The facts at a glance.

Length
7 amino acids, ring-shaped
Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH
Sold as
  • PT-141 10 mg
Regulatory status
FDA-approved in 2019 as Vyleesi, an as-needed autoinjector for premenopausal women with HSDD.
Also known as
Bremelanotide (Vyleesi)

Sources. What this page rests on.

Every source behind this page, with what it says and when it was checked, is in the Source library.

PT-141 in the Source library

Original overview and research notes · annotated 2026-10-01

Historical collection text. Read alongside the claim corrections above; identity or evidence qualifications may supersede this wording.

Sexual desire (acts on the brain)

An FDA-approved drug for low sexual desire that acts on the brain, not blood flow.

A ring-shaped seven-amino-acid peptide, nearly identical to Melanotan II. It was found when men testing Melanotan II for tanning reported erections.

It activates melanocortin receptors (mainly MC4R) in brain areas tied to sexual motivation. That’s different from Viagra-type drugs, which increase blood flow.

Two Phase 3 trials in premenopausal women with hypoactive sexual desire disorder showed modest but significant gains in desire and less distress. Earlier trials in men showed erectile effects.

Original status record: FDA-approved in 2019 as Vyleesi, an as-needed autoinjector for premenopausal women with HSDD.

Explore other research topics.

Glossary

Agonist

A molecule that activates a receptor, mimicking the body’s own signal. An antagonist blocks it.

Full glossary

Glossary

Melanocortin receptors

Five receptors (MC1R–MC5R) that control skin pigment, appetite, sexual arousal and inflammation. Targeted by the Melanotans, PT-141 and KPV.

Full glossary

Glossary

Phase 1 / 2 / 3

Stages of human drug testing: safety in a few people, then effectiveness in hundreds, then large confirmatory trials in thousands. Most compounds fail along the way.

Full glossary

Glossary

Cryo-EM

Cryo-electron microscopy. Molecules are frozen in a thin layer of ice and photographed thousands of times with an electron microscope; the images are combined into a 3D map.

Full glossary

Glossary

Resolution

How sharp a structure is, measured in ångströms (Å; a ten-billionth of a meter). Smaller is sharper.

Full glossary

Glossary

Protein Data Bank (PDB)

The free worldwide archive of 3D structures of proteins and other molecules measured in experiments. Each entry has a four-character code, like 7KI0.

Full glossary