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Acts in the brain, activating MC3 and MC4 melanocortin receptors in the hypothalamus rather than working on blood flow.
Dose ranges reflect commonly studied amounts in published research models. This is not medical advice. For research use only. Not for human consumption.
Protocol Comparison
Research Dose Reference
Available in 10mg · 100mcg per spray
PT-141 NASAL KIT
Cognitive
Research dose range
0 mcg187.5 mcg375 mcg562.5 mcg750 mcg
Standard research range
400 - 600 mcg
Four to six sprays (400–600mcg), split across both nostrils; still below the lowest injectable trial dose.
Research focus
Central melanocortin desire pathway
Observed window
On-demand onset: 30–60 min
Administration
On demand, about 45 minutes beforehand
Primary pathway
MC3R / MC4R
Doses calculated from this kit's actual concentration: 2 mg/ml, 100mcg per 0.05ml spray. Injectable reference doses from Clayton et al., 2016, and the RECONNECT Phase 3 trials (Kingsberg et al., 2019); intranasal development was halted in 2007 over blood pressure increases. Nasal-to-injectable equivalence is unestablished. For research use only.
PROTOCOL BENEFITS
Engineered Outcomes
Central desire pathway · MC4R activation · Needle-free
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The nasal route is where PT-141 began: Palatin's first clinical program tested it as an intranasal spray.
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Needle-free and pre-measured: every 0.05ml spray delivers a fixed 100mcg, so doses are counted in sprays.
SCIENCE
How It Works.
PT-141 is a cyclic analog of alpha-MSH and the active compound in Vyleesi, approved by the FDA in 2019 for low sexual desire in premenopausal women. Instead of acting on blood vessels, it activates melanocortin receptors in brain regions tied to desire and arousal.
PT-141 was first developed as a nasal spray, and early trials showed activity in both men and women. In 2007 the FDA halted the intranasal program after participants showed blood pressure increases, and development moved to the injectable form that was eventually approved.
WHAT TO EXPECT
PT-141 is used on demand, not daily. In clinical research the injectable form was given about 45 minutes beforehand, and nasal absorption is lower and less predictable than injection.
PROTOCOL NOTE
Kit includes 10mg lyophilized PT-141, 5ml sterile saline and a 0.05ml metered nasal spray bottle. Once reconstituted, keep refrigerated. For research use only. Full documentation included with every order.
FAQ
Protocol Questions
Why was the original PT-141 nasal spray discontinued?+
In 2007 the FDA halted the intranasal trials after participants showed rises in blood pressure. Developers moved to a subcutaneous injection, the form approved as Vyleesi in 2019.
Is a nasal dose equivalent to an injected dose?+
No. Less PT-141 is absorbed through the nose, which is why intranasal trials used much higher doses than the 1.75mg injection. Spray counts shouldn't be converted to injectable doses one-to-one.
How many sprays does the kit give?+
Reconstituted with 5ml saline, the kit holds 2 mg/ml: about 90 usable sprays after priming, each delivering 100mcg. Keep it to 2–3 sprays per nostril at a time.