PT 141 Peptide Therapy for Enhanced Libido Lifeforce PT 141 is the peptide men use when they want full throttle erections and the confidence that comes with knowing they'll perform. FDA approved in 2019 as Vyleesi. Pharmacy price runs over $1,000 per dose. PT 141 Side Effects, Duration, & Benefits Invigor Medical Double 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