PT-141 Side Effects: What Studies and Users Report
What FDA labels and clinical studies report for PT-141, how strong that evidence is, and what is still unknown.
Side effects reported in studies
Adverse reactions from the FDA label come first, then side effects reported in individual studies. Frequencies are quoted as the source gives them; animal results are labelled.
| Side effect | How common | Study type | Source |
|---|---|---|---|
| Nausea | 40.0% vs 1.3% placebo | FDA label | FDA label (Vyleesi) |
| Flushing | 20.3% vs 0.3% placebo | FDA label | FDA label (Vyleesi) |
| Headache | 11.3% vs 1.9% placebo | FDA label | FDA label (Vyleesi) |
| Vomiting | 4.8% vs 0.2% placebo | FDA label | FDA label (Vyleesi) |
| Nausea | 40.0% vs 1.3% (bremelanotide vs placebo) | Human RCTn = 1247 | Journal of women's health 2022, PMID 35147466 |
| Focal hyperpigmentation | more than one-third after up to 16 consecutive daily doses | Human RCTn = 1247 | Journal of women's health 2022, PMID 35147466 |
| Transient blood pressure increase“Small and transient but statistically significant blood pressure increases were observed during ambulatory blood pressure monitoring.” | Frequency not stated | Human RCTn = 1247 | Journal of women's health 2022, PMID 35147466 |
| Nausea, flushing, headache | 10% or more in both studies | Human RCTn = 1267 | Obstetrics and gynecology 2019, PMID 31599840 |
| Blood pressure increase and heart rate reduction | -4.6 to -4.7 bpm heart rate at 1.75 mg | Human RCTn = 397 | Journal of hypertension 2017, PMID 27977473 |
| Systolic blood pressure rise | 3.1 and 3.2 mmHg at 1.75 mg | Human RCTn = 397 | Journal of hypertension 2017, PMID 27977473 |
| Ethanol co-administration“No clinically significant pharmacokinetic interactions were found between ethanol and BMT either overall or by sex.” | Frequency not stated | Human RCTn = 24 | Clinical therapeutics 2017, PMID 28189361 |
| Nausea, flushing, headache“Adverse events: nausea, flushing, headache.” | Frequency not stated | Human RCTn = 327 | Women's health 2016, PMID 27181790 |
| Drug-related adverse effects“More drug related adverse effects occurred in the bremelanotide group (p = 0.01).” | Frequency not stated | Human RCTn = 342 | The Journal of urology 2008, PMID 18206919 |
| Overall tolerability“PT-141 was safe and well tolerated in both studies.” | Frequency not stated | Human RCT | International journal of impotence research 2004, PMID 14999221 |
| Flushing and nausea“Flushing and nausea were the most common adverse events reported in both studies” | Frequency not stated | Human RCT | International journal of impotence research 2004, PMID 14963471 |
What is not known
- How common each effect is at the doses people use outside of studies.
- Effects that take longer to appear than the length of the published studies.
- How PT-141 interacts with other medicines and supplements.
- Whether research-grade products, which are not checked by the FDA, behave like the material used in studies.
When to get medical help
Get urgent care for: trouble breathing, swelling of the face or throat, a widespread rash, severe or lasting stomach pain, fainting, or an injection site that becomes hot, red and spreading.
This is not a complete list. A doctor or pharmacist can help you judge whether a symptom is related.
Common questions
What are the side effects of PT-141?
The FDA label lists nausea, flushing, headache among others. The table on this page gives how often each happened and links each source.
Is PT-141 safe?
PT-141 has an FDA-approved label that lists its known risks. That label covers the approved product used as prescribed, not compounded or research-chemical versions.
More on PT-141
DosageDoses used in published studies, with the source for each.CalculatorVial, water and dose to syringe units.ResultsStudy outcomes and when they were measured.PricePrice per mg and per week from dated listings. No vendor links.Legal statusFDA, compounding and WADA status with dates.How to injectSites, syringe types and hygiene, step by step.
Sources
- 1These highlights do not include all the information needed to use VYLEESI ® safely and effectively. See full prescribing information for VYLEESI VYLEESI (bremelanotide injection), for subcutaneous use Initial U.S. Approval: 2019FDA label (Vyleesi), DailyMed · current labeldailymed.nlm.nih.govAccessed 2 Oct 2026
- 2Safety Profile of Bremelanotide Across the Clinical Development Program.Journal of women's health (2002) · 2022PMID 35147466Accessed 2 Oct 2026
- 3Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials.Obstetrics and gynecology · 2019PMID 31599840Accessed 2 Oct 2026
- 4Usefulness of ambulatory blood pressure monitoring to assess the melanocortin receptor agonist bremelanotide.Journal of hypertension · 2017PMID 27977473Accessed 2 Oct 2026
- 5Phase I Randomized Placebo-controlled, Double-blind Study of the Safety and Tolerability of Bremelanotide Coadministered With Ethanol in Healthy Male and Female Participants.Clinical therapeutics · 2017PMID 28189361Accessed 2 Oct 2026
- 6Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial.Women's health (London, England) · 2016PMID 27181790Accessed 2 Oct 2026
- 7Salvage of sildenafil failures with bremelanotide: a randomized, double-blind, placebo controlled study.The Journal of urology · 2008PMID 18206919Accessed 2 Oct 2026
- 8Evaluation of the safety, pharmacokinetics and pharmacodynamic effects of subcutaneously administered PT-141, a melanocortin receptor agonist, in healthy male subjects and in patients with an inadequate response to Viagra.International journal of impotence research · 2004PMID 14999221Accessed 2 Oct 2026
- 9Double-blind, placebo-controlled evaluation of the safety, pharmacokinetic properties and pharmacodynamic effects of intranasal PT-141, a melanocortin receptor agonist, in healthy males and patients with mild-to-moderate erectile dysfunction.International journal of impotence research · 2004PMID 14963471Accessed 2 Oct 2026
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