Triptorelin

A synthetic GnRH agonist decapeptide analog with a D-Trp6 substitution that provides greatly enhanced potency and resistance to enzymatic degradation compared to native GnRH. After an initial stimulatory phase, chronic administration causes pituitary GnRH receptor downregulation, leading to profound suppression of gonadotropins and sex steroid production.

• D-Trp6 substitution makes the peptide resistant to enzymatic cleavage, increasing potency ~100-fold over native GnRH
• Acute administration causes a flare: robust release of LH and FSH from pituitary gonadotrophs
• Chronic continuous exposure downregulates and desensitizes GnRH receptors, suppressing LH, FSH, and downstream sex steroids

• Pregnancy (Category X)
• Known hypersensitivity to GnRH or GnRH analogs
• Undiagnosed vaginal bleeding
• Osteoporosis or significant bone density loss

Store depot formulations at room temperature (20–25°C (68–77°F)). Lyophilized research-grade peptide: store at 2–8°C (36–46°F) for up to 3 months or -20°C (-4°F) long-term. Once reconstituted, refrigerate and use promptly.

Depot formulations come as pre-mixed suspensions. Research-grade lyophilized powder should be reconstituted with bacteriostatic water or sterile saline.

Triptorelin is FDA-approved under multiple brand names (Trelstar, Decapeptyl) for advanced prostate cancer, endometriosis, and central precocious puberty. In the peptide research community, it has gained interest due to a small 2009 study by Tan & Scally suggesting that a single low-dose (100 mcg) injection could significantly stimulate endogenous testosterone recovery after anabolic steroid-induced hypogonadism. While this application remains under-studied, the compound's clinical pharmacology is well-established.