Triptorelin is a synthetic decapeptide analogue of Gonadotropin-Releasing Hormone (GnRH). The 11.25mg formulation is a long-acting, sustained-release depot injection used for the palliative treatment of advanced hormone-dependent prostate cancer and for the management of central precocious puberty. It acts as a potent GnRH agonist, initially stimulating then profoundly suppressing pituitary gonadotropin secretion, leading to a medical castration or suppression of puberty.
Adult: Prostate Cancer: 11.25mg as a single intramuscular (IM) injection into the gluteal region every 3 months (84 days). Pre-treatment with an oral anti-androgen for at least 2 weeks before and 2-4 weeks after the first injection is recommended.
Note: For IM use only. Reconstitute the microsphere powder with the provided sterile diluent (typically 2mL). Shake well to form a uniform milky suspension. Adminish immediately via deep IM injection into the upper outer quadrant of the gluteus. Do not inject intravenously. Rotate injection sites.
Triptorelin is a superagonist of the endogenous GnRH receptor. Continuous, non-pulsatile stimulation of pituitary GnRH receptors leads to an initial flare (upregulation) followed by profound downregulation and desensitization of these receptors. This inhibits the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In males, the suppression of LH leads to a dramatic reduction in testicular testosterone production (medical castration). In central precocious puberty, it halts the premature activation of the hypothalamic-pituitary-gonadal axis.
Pregnancy: CONTRANDICATED - Category X. May cause fetal harm based on mechanism. Can cause spontaneous abortion. Exclude pregnancy before starting. Women of childbearing potential must use non-hormonal contraception during and for several months after treatment.
Driving: May cause fatigue, dizziness, or visual disturbances. Patients should be cautious until they know how the drug affects them.
| Bicalutamide, Flutamide | Concomitant use is standard to block the initial testosterone flare. Synergistic therapeutic effect. | Major (Beneficial) |
| Corticosteroids (e.g., Dexamethasone) | May suppress ACTH and reduce the efficacy of triptorelin. Monitor. | Moderate |
| Drugs that prolong QT interval (e.g., Class IA/III antiarrhythmics, certain antipsychotics, antibiotics) | Additive risk of QT prolongation. Monitor ECG and electrolytes. | Moderate |
| Sex hormones (androgens, estrogens) | Counteracts the therapeutic effect of triptorelin. Contraindicated. | Major |
Same composition (Triptorelin (11.25mg)), different brands: