Strong evidence · Grade A
PT-141 / Bremelanotide
PT-141 (Bremelanotide)
Score
79 / 100
Dosing
As needed
Brand
Vyleesi
FDA
2019
TL;DR
01
A melanocortin receptor agonist, FDA-approved in 2019 as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women — taken as needed, not daily.
02
Approval rests on two phase 3 RCTs (RECONNECT, ~1,270 women): it significantly increased sexual desire and reduced related distress versus placebo.
03
One real caveat: the effect size is modest — a ~0.3-point rise on the desire scale — and whether that is life-changing is genuinely debated.
04
The main downside is tolerability: about 40% of women had nausea, and it can transiently raise blood pressure and, with repeated use, cause skin darkening.
05
Unlike the grey-market melanotan peptides it descends from, PT-141 is an approved, regulated medicine for a specific indication.
Desire increase (RECONNECT)
+0.35
FSFI-desire · significant vs placebo
Distress reduction
−0.33
FSDS-DAO item 13 · significant
Nausea
~40%
main tolerability issue
Approved use
HSDD (premenopausal)
women only
Dosing
PRN, ≤8/month
subcutaneous, ~45 min before
Part 01 · How it works
Mechanism.
PT-141 (bremelanotide) works in the brain rather than on blood flow. It activates melanocortin receptors — especially MC4R — in circuits that regulate sexual desire, which is why it's used for low desire rather than for erections specifically. It's taken on demand, about 45 minutes ahead, not every day. Because melanocortin receptors also control pigmentation and blood pressure, those show up as its main side effects: skin darkening with repeated use and a transient rise in blood pressure.
Most sexual-function drugs work on the plumbing; PT-141 works on the 'interest' switch in the brain. Turning that switch also nudges the pigment and blood-pressure systems that share the same wiring.
MC4R agonism
Activates melanocortin-4 (and MC3) receptors in CNS pathways governing sexual desire — a central, not vascular, mechanism.
On-demand use
Subcutaneous, as-needed dosing ~45 min before anticipated activity; not daily.
Pigmentation effect
MC1R cross-activity causes focal hyperpigmentation with repeated dosing, more likely in darker skin types.
Cardiovascular effect
Transient rise in blood pressure and small heart-rate drop after each dose — the basis for its cardiovascular contraindications.
Part 02 · Dosing & administration
How it's taken.
Clinical · trial-validatedValues below describe how PT-141 / Bremelanotide has been administered in human clinical trials and/or approved labeling. Provided for educational purposes only — this is not medical advice and not instructions for self-administration. Consult your healthcare provider before making any health decision.
As needed
1.75 mg
Subcutaneous, ~45 min before anticipated activity; max one dose/24 h and ≤8/month.
·
Doses below are from labeling, not instructions.
·
On-demand (PRN) medicine — not a daily treatment.
·
Avoid a second dose within 24 hours and limit to 8 doses per month per labeling.
Need help with reconstitution?
Use the free peptide calculator for dilution, unit conversion, and injection volume.
Part 03 · Safety
Side effects, rare serious events, who shouldn't.
Common
Nausea
Most common; a frequent reason for discontinuation. Often worst with the first dose.
~40%
Flushing
Common, transient.
~20%
Headache
Common, transient.
~11%
Injection-site reactions
Generally mild.
Common
Serious · rare
Transient blood-pressure increase
Contraindicated in uncontrolled hypertension or known cardiovascular disease.
Expected per dose
Focal hyperpigmentation
Darkening of face, gums, breasts; more likely with more doses and in darker skin types; may not fully resolve.
With repeated use
Nausea-related discontinuation
Not dangerous but the leading tolerability-driven dropout.
Notable
Absolute · do not use
×
Uncontrolled hypertension
×
History of melanoma or atypical mole syndrome
×
Cardiovascular disease (myocardial infarction, stroke within past 6 months)
×
Pregnancy or breastfeeding
×
Known hypersensitivity to bremelanotide or any component
×
Concurrent use with other melanocortin receptor agonists
Relative · discuss first
!
Uncontrolled hypertension or known cardiovascular disease — contraindicated (blood-pressure effect)
!
Postmenopausal women or men — not an approved population
!
HSDD from a coexisting medical/psychiatric condition, relationship issue, or medication — not indicated
!
Higher cardiovascular-risk individuals — weigh the transient BP rise carefully
Interactions
Antihypertensives
Bremelanotide causes transient blood pressure increase; may oppose antihypertensive therapy. Per FDA label, use with caution in patients with cardiovascular disease
Moderate
PDE5 inhibitors (sildenafil, tadalafil)
Additive effects on sexual function; risk of hypotension due to opposing vascular effects. FDA labeling recommends against concurrent use with PDE5 inhibitors
Major
Naltrexone
Per FDA label, bremelanotide may reduce the systemic exposure of oral naltrexone; avoid concurrent use
Major
Other melanocortin agonists (Melanotan II)
Additive melanocortin receptor activation; increased risk of nausea, flushing, and hypertension
Moderate
Labs to monitor
Blood Pressure
Before and after each dose initially
PT-141 can cause transient hypertension
CMP (Comprehensive Metabolic Panel)
Baseline and every 6 months
Liver and kidney function
Dermatological Exam
Baseline and annually
Melanocortin agonist — monitor for skin changes
CBC with Differential
Baseline and every 6 months
General safety monitoring
Part 04 · Evidence
How strong is the evidence?
79
Grade A
Grade A for evidence quality — two well-run phase 3 RCTs and FDA approval — tempered by a modest effect size and real tolerability limits. It works, and it's regulated; the open question is how much it helps any given person.
Mechanistic plausibility
Central melanocortin control of sexual desire is well supported.
82
Human evidence
Two identical phase 3 RCTs (RECONNECT, n≈1,270) plus earlier trials; FDA-approved.
85
Effect size
Statistically significant but modest (~0.3-point desire increase); clinical meaningfulness is debated.
62
Safety & tolerability
Nausea ~40%, transient blood-pressure rise, and hyperpigmentation with repeated use; manageable but real.
72
Independence
Pivotal trials industry-sponsored; regulatory review adds independent scrutiny.
70
Part 05 · Research log
Every study we cite.
We list each study with its methodology, funding source, and our quality grade. Flagged studies aren't dismissed — they're tagged so you can weigh them.
01
2019
Obstetrics & Gynecology Industry funded
Bremelanotide for HSDD — two randomized phase 3 trials (RECONNECT)
Bremelanotide 1.75 mg significantly increased FSFI-desire (+0.35) and reduced desire-related distress (−0.33) vs placebo; nausea, flushing, and headache were the most common adverse events.
Two identical phase 3 RCTs, 24 wk, placebo-controlled, PRN dosing · n = 1,267 · Sponsored by Palatin/AMAG; statistically significant but modest effect sizes.
PMID 31599840 ↗
High
02
2000
Urology Flagged
Melanotan II (parent compound) on erection and desire in men with ED
The parent melanocortin agonist induced erections and increased desire vs placebo, establishing central melanocortin effects on sexual function — with frequent nausea.
Double-blind, placebo-controlled crossover · n = 10 · Small mechanistic study of the precursor; foundational for the class.
PMID 11018622 ↗
Moderate
Evidence against
What didn't work, and where the evidence is thin.
Every publication is incentivized to tell you a peptide works. We catalogue the null results, failed trials, and mechanism limits we found in the same literature — so you can weigh them against the upside, with your provider.
01
Modest effect size — significant, but is it meaningful?
Mechanism limit Obstet Gynecol (RECONNECT) · 2019
The improvement in desire was about 0.3 points on the FSFI-desire scale — statistically significant but small, and the responder/clinical-meaningfulness of that change has been questioned in independent commentary.
What this means: PT-141 is a real, approved option, but expectations should be calibrated: on average the desire benefit is modest, not transformative.
PMID 31599840 ↗
02
Tolerability and cardiovascular limits
Safety signal Obstet Gynecol (RECONNECT) · 2019
About 40% of women had nausea (a common reason for discontinuation), and the drug transiently raises blood pressure — so it is contraindicated in uncontrolled hypertension or known cardiovascular disease. Repeated dosing can cause focal skin darkening.
What this means: The side-effect and blood-pressure profile meaningfully narrows who should use it and how often (no more than 8 doses/month, not within 24 hours of another dose).
PMID 31599840 ↗
Part 06 · Cost & access
Where it's available, at what price.
United States
FDA-approved
Rx as Vyleesi for premenopausal HSDD. Prescribed via gynecology/primary care.
Brand pricing; coverage for the indication varies
European Union
Not approved
Not approved for HSDD in the EU.
N/A
United Kingdom
Not approved
Not approved for HSDD.
N/A
Canada
Not approved
Not approved for HSDD.
N/A
The Peptide Column takes no affiliate commission from any source. PT-141 (Vyleesi) is a prescription-only medicine approved for premenopausal HSDD; grey-market 'PT-141' sold for other uses or to other populations is off-label and unregulated. We link only to clinician-directed care, never to sellers.
Part 07 · Your appointment
Questions to bring.
01
Am I a candidate for bremelanotide based on the FDA-approved indication?
02
How does bremelanotide compare to flibanserin for HSDD?
03
What are the blood pressure monitoring requirements?
04
How often can bremelanotide be safely used per month?
References
Every citation, numbered.
Citation list. For our editorial read of each study — including bias flags and quality grades — see the Research log above.
- 01. Bremelanotide for HSDD — two randomized phase 3 trials (RECONNECT) · Obstetrics & Gynecology, 2019 · PMID 31599840 ↗
- 02. Melanotan II (parent compound) on erection and desire in men with ED · Urology, 2000 · PMID 11018622 ↗
- 03.
- 04.