Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction: double-blind, placebo controlled crossover study.
Level 2 - randomized trial
Double-blind, placebo-controlled crossover trial
What was done
Ten men with psychogenic erectile dysfunction (no known organic cause) participated in a double-blind, placebo-controlled crossover study. Participants received injections of Melanotan-II (0.025 mg/kg), a cyclic alpha-melanocyte-stimulating hormone analogue, or vehicle placebo. Erectile response was assessed over a 6-hour period using real-time RigiScan monitoring to measure presence, duration, and rigidity.
What was found
Clinically apparent erections developed in 8 of 10 men after Melanotan-II administration. The mean duration of penile tip rigidity greater than 80% was 38.0 minutes with Melanotan-II compared to 3.0 minutes with placebo (p = 0.0045). Transient adverse effects including nausea, stretching, yawning, and decreased appetite occurred more frequently with Melanotan-II than placebo, but none required medical intervention.
Why it matters
This study provided early clinical proof-of-concept that central melanocortin receptor agonists can stimulate erections in humans with psychogenic erectile dysfunction.
Limits
The study sample was extremely small (n = 10) and limited entirely to men with non-organic (psychogenic) erectile dysfunction, precluding generalization to organic ED. Long-term safety, optimal dosing regimens, and outcomes outside a controlled 6-hour laboratory setting were not evaluated.
Cited by
- supports Melanotan II stimulates strong penile erections.