Everything you need to know about peptide therapies

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist approved for type 2 diabetes and chronic weight management. It represents the leading edge of the incretin-based therapy revolution and has become one of the most widely prescribed peptide therapeutics globally. Available in both injectable (Ozempic, Wegovy) and oral (Rybelsus) formulations.

Tirzepatide is a dual glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptor agonist approved for type 2 diabetes and chronic weight management. It represents a novel dual-incretin approach that has demonstrated superior weight loss and glycemic control compared to selective GLP-1 agonists in multiple Phase III trials.

Sermorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) consisting of the first 29 amino acids of the 44-amino acid GHRH sequence. Originally FDA-approved for diagnostic use in assessing growth hormone secretion, it has become a cornerstone of legitimate peptide therapy for growth hormone optimization due to its established safety profile and compounding eligibility.

Tesamorelin is a synthetic GHRH analog that is the only FDA-approved peptide therapy specifically for the reduction of excess abdominal fat. Originally approved for HIV-associated lipodystrophy, it has gained significant attention in the anti-aging and metabolic optimization space as a legal, well-characterized GH secretagogue.

PT-141 (bremelanotide) is a melanocortin receptor agonist FDA-approved as Vyleesi for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women. It is unique among sexual health therapeutics in that it acts centrally through the nervous system rather than peripherally on blood flow.

Liraglutide is a GLP-1 receptor agonist FDA-approved for type 2 diabetes (Victoza) and chronic weight management (Saxenda). As an acylated GLP-1 analog with 97% homology to native GLP-1, it was one of the first once-daily GLP-1 agonists to gain widespread clinical adoption and paved the way for longer-acting agents like semaglutide.

Exenatide is a synthetic form of exendin-4, a peptide originally isolated from Gila monster venom, and was the first GLP-1 receptor agonist approved by the FDA. Available as twice-daily (Byetta) and once-weekly (Bydureon) formulations, it established the GLP-1 agonist class as a cornerstone of diabetes management.

Pentosan polysulfate sodium (PPS) is a semi-synthetic heparinoid glycosaminoglycan FDA-approved as Elmiron for interstitial cystitis/bladder pain syndrome. While not a peptide per se, it is widely offered by peptide therapy clinics for its tissue-repair and anti-inflammatory properties, particularly for joint health and osteoarthritis. It has a long clinical track record dating to the 1990s.

Bremelanotide is a synthetic melanocortin receptor agonist FDA-approved (Vyleesi) for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women. It is the commercially developed form of the research peptide PT-141. Unlike PDE5 inhibitors, it acts centrally through melanocortin pathways in the brain to enhance sexual desire rather than peripheral vascular mechanisms.

Oxytocin is a nine-amino acid endogenous neuropeptide hormone produced in the hypothalamus and released by the posterior pituitary. FDA-approved (Pitocin) for labor induction and postpartum hemorrhage, it is also widely investigated for social bonding, anxiety, autism spectrum disorder, PTSD, and relationship enhancement. It plays a central role in maternal bonding, social cognition, and stress regulation.