PT141
Bremelanotide
PT-141, also known as Bremelanotide, is a synthetic peptide derived from Melanotan II (MT-II), originally developed to stimulate melanin production for skin tanning. However, during research, it was discovered that PT-141 had powerful effects on sexual arousal and libido, making it a promising treatment for sexual dysfunction in both men and women. Unlike PDE5 inhibitors such as sildenafil (Viagra) or tadalafil (Cialis), which work by increasing blood flow to the genital area, PT-141 acts directly on the central nervous system, stimulating the melanocortin receptors (MC3R and MC4R) in the brain to enhance sexual desire and arousal.
PT-141 was approved by the FDA in 2019 under the brand name Vyleesi for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women. It has also been studied as a potential treatment for erectile dysfunction (ED) in men, particularly in cases where traditional PDE5 inhibitors have failed. Additionally, emerging research suggests that PT-141 may have secondary benefits, such as improving mood, increasing energy levels, and reducing appetite due to its activation of melanocortin receptors.
Protocols
1. Sexual Enhancement (Men & Women)
Dosage: 0.5–2 mg per injection, as needed (1–3 hours before activity)
Cycle: Used on demand or as part of a regular protocol (e.g., 2–3 times per week)
Administration: Subcutaneous (SC) injection, usually in the abdomen or thigh
Stacking: Can be combined with sildenafil (Viagra) or tadalafil (Cialis) for improved erectile function in men
Expected Benefits: Increased libido, enhanced sexual arousal, stronger and longer-lasting erections in men, heightened sexual sensitivity in women
2. Erectile Dysfunction (ED) Treatment (Men)
Dosage: 1–2 mg per injection, 2–3 times per week
Cycle: 4–6 weeks, with breaks as needed
Administration: SC injection, ideally 1–2 hours before sexual activity
Stacking: Works well with arginine, citrulline, or NO boosters to enhance blood flow
Expected Benefits: Increased erection quality, improved response in men who do not respond well to PDE5 inhibitors
3. Hypoactive Sexual Desire Disorder (HSDD) in Women
Dosage: 1.75 mg per injection, used as needed (FDA-approved dose for HSDD)
Cycle: Used on demand, up to 8 times per month
Administration: SC injection
Stacking: Can be used with hormonal therapies or testosterone in postmenopausal women
Expected Benefits: Increased sexual desire and responsiveness, reduced psychological distress related to low libido
4. Mood Enhancement & Energy Boosting
Dosage: 0.5–1 mg per injection, 2–3 times per week
Cycle: 4–6 weeks, with reassessment
Administration: SC injection
Stacking: Works well with MOTS-c or NAD+ precursors for energy and anti-ageing benefits
Expected Benefits: Improved mood, reduced stress, increased motivation and energy levels
Further reading
PT-141 functions primarily as a melanocortin receptor agonist, acting on the MC3R and MC4R receptors in the brain. These receptors play a key role in regulating sexual function, mood, and energy homeostasis. Unlike PDE5 inhibitors, which require physical stimulation to work, PT-141 directly stimulates sexual desire by enhancing neural pathways associated with arousal. This makes it effective even in cases where traditional ED treatments have failed, such as in patients with psychological or neurogenic erectile dysfunction.
Studies on PT-141 have shown that it significantly increases sexual motivation and responsiveness in both men and women, making it one of the few treatments available for female sexual dysfunction. Clinical trials leading to its FDA approval demonstrated that women with HSDD reported higher levels of sexual desire, improved satisfaction, and reduced distress related to low libido after using PT-141.
Beyond its effects on sexual function, PT-141’s activation of melanocortin receptors suggests it may have additional physiological benefits. Some research indicates it may help regulate appetite, reduce inflammation, and enhance cognitive function. However, these effects require further investigation.
Potential Side Effects
Nausea (most common, reported in ~40% of users, usually mild and transient)
Flushing or warmth sensation
Increased blood pressure (short-term effect)
Fatigue or dizziness
Spontaneous erections (in men)
While generally well-tolerated, PT-141 should be used cautiously in individuals with cardiovascular issues, hypertension, or a history of stroke, as it can cause mild increases in blood pressure.
References
- Wessells, H., et al. (2000). "Melanocortin receptor agonists: The next generation of therapies for erectile dysfunction?" International Journal of Impotence Research, 12(S4), S64–S69.
Kingsberg, S. A., et al. (2019). "Bremelanotide for the treatment of hypoactive sexual desire disorder in premenopausal women: A phase 3 randomized controlled trial." Obstetrics & Gynecology, 134(5), 899–908.
Hadley, M. E., et al. (2006). "PT-141: The first effective treatment for female sexual dysfunction?" Expert Opinion on Investigational Drugs, 15(2), 156–160.
Safarinejad, M. R. (2008). "Evaluation of the efficacy, safety and tolerability of the melanocortin receptor agonist PT-141 in treatment of male erectile dysfunction." BJU International, 101(2), 251–256.
Dorr, R. T., et al. (2004). "The pharmacokinetics and safety of Bremelanotide (PT-141) in human subjects." Clinical Pharmacology & Therapeutics, 76(1), 66–73.