How does PT-141 nasal spray compare with the injection?
FAQOnly the injection is approved. Vyleesi, a 1.75 mg subcutaneous autoinjector, has about 100% bioavailability by its label, and no nasal bremelanotide product appears in Drugs@FDA or DailyMed. Intranasal PT-141 was tested in small trials at 7.5–20 mg; in a 2004 study, erections were significant above 7 mg, beginning in about 30 minutes.
On this page
The approved product
Vyleesi (NDA 210557, approved June 21, 2019) is a subcutaneous autoinjector for premenopausal women with acquired, generalized hypoactive sexual desire disorder. Its label sets a 1.75 mg dose into the abdomen or thigh, as needed, at least 45 minutes before anticipated sexual activity, and reports absolute bioavailability of about 100% after subcutaneous injection. A search of Drugs@FDA and DailyMed for bremelanotide on October 7, 2026, returned this product only.
For the adverse events reported at these doses, see PT-141 side effects.
What the intranasal trials found
Palatin, the developer, ran its early trials with a nasal spray. A 2004 double-blind study in healthy men and men with erectile dysfunction found erections significantly greater than placebo at doses above 7 mg, with the first erection in about 30 minutes and flushing and nausea the most common adverse events. A 2005 crossover study of 19 men combined 7.5 mg intranasal PT-141 with 25 mg sildenafil, and a 2006 study gave 18 premenopausal women a single 20 mg intranasal dose.
A 2017 safety study with alcohol reported that the 20 mg intranasal dose gives exposure about 1 to 2 times that of the subcutaneous dose then in phase III. By Prof. Peptide's arithmetic, that is roughly 11 times the milligrams of the 1.75 mg injection for similar exposure. The published record read for this page does not state why development moved from the nasal spray to the injection.
The flagged nasal papers
Two 2008 papers by one author tested intranasal bremelanotide. The Journal of Sexual Medicine study in women has been retracted. The Journal of Urology study, in 342 men who had not responded to sildenafil, has carried an expression of concern since 2023. Neither is relied on here.
What is sold
On October 7, 2026, Prof. Peptide counted PT-141 spray products at 11 of the 71 vendor catalogs it could read. No regulator has approved a nasal form, and the spray products are not the formulation used in the trials above.
Sources
Primary
- Vyleesi prescribing information, DailyMed set f1d0c1b5-2f39-4bad-a6a4-0066e3ad5dcf; Drugs@FDA NDA 210557 → — 1.75 mg subcutaneous, about 100% bioavailability; approval date from openFDA
- Diamond LE et al. Intranasal PT-141 in healthy males and patients with erectile dysfunction. Int J Impot Res 2004 (PMID 14963471) → — significant above 7 mg, onset about 30 minutes
- Diamond LE et al. Intranasal PT-141 with sildenafil. Urology 2005 (PMID 15833522) → — 7.5 mg intranasal with 25 mg sildenafil, 19 men
- Diamond LE et al. Bremelanotide in premenopausal women. J Sex Med 2006 (PMID 16839319) → — single 20 mg intranasal dose, 18 women
- Clayton AH et al. Bremelanotide coadministered with ethanol. Clin Ther 2017 (PMID 28189361) → — 20 mg intranasal ≈ 1–2× the subcutaneous exposure
Secondary
- Safarinejad MR. J Sex Med 2008 (PMID 18179455), retracted → — retraction status
- Safarinejad MR, Hosseini SY. J Urol 2008 (PMID 18206919), expression of concern 2023 → — expression-of-concern status
For other common questions regarding PT-141, see the full PT-141 profile.
Where to Buy
ILS Laboratories · batch COAs
Kovera, Chromate and BioRegen · certificates checked at each lab
Batch-traceable COAs · cold-chain shipping
Research use only. Not medical advice.
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