PT-141 (Bremelanotide) vs Thymalin
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
PT-141 (Bremelanotide)
PT-141, also known as Bremelanotide, is a synthetic peptide analog of alpha-melanocyte-stimulating hormone. It is the only FDA-approved treatment for hypoactive sexual desire disorder (HSDD) in premenopausal women.
Full details →Thymalin
Thymalin is a polypeptide preparation derived from calf thymus. Developed in Russia, it has been used for decades to support immune function and has shown potential anti-aging effects in long-term studies.
Full details →Side-by-Side Comparison
| Aspect | PT-141 (Bremelanotide) | Thymalin |
|---|---|---|
| Mechanism | PT-141 activates melanocortin receptors (MC3R and MC4R) in the central nervous system, particularly in areas associated with sexual arousal. Unlike PDE5 inhibitors, it works through the nervous system rather than the vascular system. | Regulates the ratio of T-cell subpopulations, stimulates cellular immunity, and enhances phagocytosis. Also affects neuroendocrine regulation and may influence melatonin production. |
| Typical Dosage | FDA-approved dose: 1.75mg administered subcutaneously at least 45 minutes before anticipated sexual activity. Not to be used more than once within 24 hours or more than 8 times per month. | Clinical protocols: 5-20mg daily intramuscularly for 3-10 days. Often cycled 1-2 times per year for maintenance. |
| Administration | Subcutaneous injection in the abdomen. Available as Vyleesi (commercial product). Research use may involve different dosing protocols. | Intramuscular injection. Usually administered in short courses rather than continuously. Often combined with Epithalamin for anti-aging protocols. |
| Side Effects | Common side effects include nausea (40% of users), flushing, headache, and injection site reactions. Transient blood pressure increases may occur. | Generally well-tolerated. May cause injection site reactions or temporary flu-like symptoms as immune function is modulated. |
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