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The dad-test answer
Both Vyleesi and Addyi are FDA-approved for premenopausal HSDD (low sexual desire), but they work differently. Vyleesi (bremelanotide / PT-141) is an on-demand subQ injection taken before sex. Addyi (flibanserin) is a daily oral pill that requires weeks of buildup and full alcohol avoidance. Vyleesi is the easier protocol for most women - on-demand, no daily commitment, no alcohol restriction.
Who wins for what
| Use case | Who wins, and why |
|---|---|
| on-demand use (situational low desire) |
vyleesi Single subQ injection 45 minutes before sex; no daily dosing required. |
| daily, baseline desire support |
addyi Daily oral pill maintains a steady serotonergic effect; works for women who want continuous treatment rather than situational. |
| alcohol-tolerant protocol |
vyleesi Addyi has a black-box alcohol interaction warning; Vyleesi has no equivalent restriction. |
| pill format / no injection |
addyi Oral tablet vs subQ autoinjector - Addyi is the answer for needle-averse patients. |
What the head-to-head data shows
Both molecules are FDA-approved for HSDD (Hypoactive Sexual Desire Disorder) in premenopausal women. Vyleesi (bremelanotide, the synthetic peptide PT-141) was approved in 2019 based on the RECONNECT trials - paired Phase 3 studies showing improved Female Sexual Function Index scores vs placebo when taken on demand. Addyi (flibanserin) was approved in 2015 based on three Phase 3 trials - daily oral dosing, mechanism via 5-HT1A agonism and 5-HT2A antagonism. Addyi carries a black-box warning for severe hypotension and syncope when combined with alcohol; the original REMS program required prescriber and pharmacy certification, later relaxed in 2019 with revised label. Bremelanotide is technically the only true peptide treatment in this comparison - flibanserin is included because patients with HSDD compare them directly.
Our honest call
For most women presenting with situational HSDD, Vyleesi is the cleaner protocol - take it 45 minutes before sex, no daily commitment, no alcohol avoidance. Addyi makes sense for women who want continuous baseline treatment, who are needle-averse, or who do not drink and prefer an oral. The most important framing: both are FDA-approved, both went through Phase 3 trials, both are real medicine, and both are dramatically under-prescribed because of awkward conversations and physician unfamiliarity. The PT-141 starter guide covers the Vyleesi side in depth.
Sources and citations
- FDA Vyleesi prescribing label (approved Jun 2019)
- RECONNECT-301 and RECONNECT-302 Phase 3 trials, Obstet Gynecol 2019
- FDA Addyi prescribing label (approved Aug 2015, revised 2019)
- Stahl et al., flibanserin mechanism review, J Sex Med 2011
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Last reviewed · 2026-05-07 · Page generated by Protocol One matrix engine. None of this replaces a doctor. Peptides are gray-market in the US for most uses. Talk to a real prescriber before you change anything.