ThePeptide Examiner
Comparison

PT-141 vs sildenafil: central desire vs peripheral blood flow

Two FDA-approved drugs for sexual dysfunction, targeting completely different mechanisms. Complement each other more than they compete.

Editorially reviewedThe Peptide Examiner editorial team, Editorial review · Reviewed Apr 23, 2026

PT-141 (bremelanotide, brand Vyleesi) and sildenafil (brand Viagra) are both FDA-approved treatments for sexual dysfunction — but they target entirely different components of the sexual-response system. Sildenafil is a PDE5 inhibitor that acts peripherally on vascular smooth muscle to support erectile function. PT-141 is a melanocortin receptor agonist that acts centrally on CNS pathways involved in sexual desire and arousal.

FieldPT-141 (bremelanotide)Sildenafil
Brand namesVyleesiViagra, Revatio
ManufacturerAMAG Pharmaceuticals (now Palatin Technologies)Pfizer (and generics)
FDA approved2019 (HSDD in premenopausal women)1998 (erectile dysfunction); 2005 (pulmonary hypertension)
IndicationHypoactive sexual desire disorder (premenopausal women)Erectile dysfunction; pulmonary arterial hypertension
MechanismMelanocortin receptor agonist (central)PDE5 inhibitor (peripheral vascular smooth muscle)
DeliveryOn-demand subcutaneous injection (before sexual activity)Oral tablet, on-demand

Primary sources

Frequently asked

Can they be used together?

Theoretically yes — they act on different systems. PT-141's prescribing information cautions about cardiovascular considerations (transient blood pressure effects), so combining with sildenafil requires clinician input. The combination is not a standard prescribing pattern.

Why is PT-141 only approved for women?

The RECONNECT Phase 3 trials enrolled premenopausal women with HSDD; FDA approval mirrored the trial population. Development in men for ED preceded the women's program but wasn't pursued to approval. Off-label use in men occurs but isn't backed by large FDA-approved trials.

Which has worse side effects?

PT-141 has a meaningful side-effect profile: nausea (40% of users), flushing, temporary skin darkening (off-target MC1R activation), and transient blood pressure elevation. Sildenafil is generally well-tolerated with headache, flushing, and dyspepsia as common mild side effects. For most patients, sildenafil has the cleaner profile.