LEUPROLIDE ACETATE
Clinical safety rating: avoid
Contraindicated (not allowed)
Leuprolide acetate is a synthetic gonadotropin-releasing hormone (GnRH) agonist. Upon continuous administration, it suppresses pituitary gonadotropin secretion by downregulating GnRH receptors, leading to decreased luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, and consequently reducing sex steroid (testosterone and estrogen) production in the gonads.
| Metabolism | Leuprolide is a synthetic peptide that is metabolized via peptidase-mediated hydrolysis, primarily in the liver and kidneys. Enzymes involved include endopeptidases and exopeptidases. Less than 5% is excreted unchanged in urine. |
| Excretion | Renal: approximately 5% as unchanged drug; hepatic metabolism accounts for the majority of clearance, with metabolites excreted renally and fecally; biliary excretion is minimal. |
| Half-life | Terminal elimination half-life is approximately 3 hours following intravenous administration; after subcutaneous depot formulations, the effective half-life is extended due to slow release, with a terminal half-life of about 3-4 weeks for the 1-month depot. |
| Protein binding | Approximately 43-49% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Volume of distribution is approximately 27-31 L (0.4 L/kg assuming 70 kg), indicating distribution into total body water. |
| Bioavailability | Short-acting subcutaneous injection: nearly 100%; depot intramuscular injection: approximately 90%; depot subcutaneous injection: approximately 90%. |
| Onset of Action | For short-acting subcutaneous injection, initial LH surge occurs within 1-2 hours; for depot intramuscular or subcutaneous injection, clinical suppression of testosterone or estradiol occurs within 2-4 weeks. |
| Duration of Action | For depot formulations, duration is dependent on the preparation: 1-month depot provides suppression for approximately 4 weeks; 3-month and 6-month depots provide suppression for 12 and 24 weeks, respectively. Continuous therapy maintains suppression; discontinuation leads to recovery of gonadal function typically within months. |
| Molecular Weight | 1209.4 |
Prostate cancer: 7.5 mg IM once monthly or 22.5 mg IM once every 3 months or 45 mg SC once every 6 months. Central precocious puberty: 50 mcg/kg/day SC or 7.5 mg IM once monthly. Endometriosis: 3.75 mg IM once monthly or 11.25 mg IM once every 3 months.
| Dosage form | SOLUTION |
| Renal impairment | No dose adjustment required for any degree of renal impairment. |
| Liver impairment | No dose adjustment required for any degree of hepatic impairment based on Child-Pugh classification. |
| Pediatric use | Central precocious puberty: Initial dose 50 mcg/kg/day SC; if inadequate suppression, increase by 10 mcg/kg/day; maximum 100 mcg/kg/day. Alternatively, IM leuprolide acetate depot 7.5 mg every 28 days for body weight ≥25 kg; 11.25 mg every 28 days for body weight <25 kg. |
| Geriatric use | No dose adjustment required; administer standard adult dosing. Monitor for potential increased sensitivity to cardiovascular effects and bone density loss. |
| 1st trimester | Risk of early pregnancy loss; contraindicated due to potential teratogenicity. |
| 2nd trimester | Risk of fetal harm; contraindicated. |
| 3rd trimester | Risk of fetal harm; contraindicated. |
Clinical note
No significant drug interactions Causes an initial increase in testosterone levels which may worsen symptoms in prostate cancer patients.
| Placental transfer | Leuprolide acetate is a small peptide that likely crosses the placenta; animal studies have shown fetal exposure and adverse effects. |
| Breastfeeding | Leuprolide acetate is excreted in human milk; due to potential adverse effects in nursing infants, breastfeeding is not recommended during treatment. |
| Lactation Rating |
■ FDA Black Box Warning
No FDA black box warning is required for leuprolide acetate; however, labeling includes warnings about tumor flare (transient increase in serum testosterone/estrogen) and an increased risk of diabetes, cardiovascular events, and stroke in men receiving GnRH agonists for prostate cancer.
| Common Effects | endometriosis |
| Serious Effects |
PregnancyHypersensitivity to leuprolide acetate or any component of the formulationUndiagnosed abnormal vaginal bleeding (for women of reproductive potential)
| Precautions | Tumor flare: Transient worsening of symptoms (e.g., bone pain, urinary obstruction) during initial therapy in prostate cancer, Hyperglycemia and increased risk of diabetes mellitus, Cardiovascular risks: Myocardial infarction, sudden cardiac death, stroke (especially in men), Bone loss: Decreased bone mineral density with prolonged use (osteoporosis, fracture risk), Hypersensitivity reactions (angioedema, anaphylaxis), Seizures have been reported in patients with epilepsy or underlying CNS disorders, Psychiatric effects (mood changes, depression), Injection site reactions (pain, erythema, abscess), Pituitary apoplexy (rare but serious, especially in patients with pituitary adenoma), QT interval prolongation caution in patients with electrolyte abnormalities or on QT-prolonging drugs |
Loading safety data…
| L5 (Contraindicated) |
| Teratogenic Risk | Leuprolide acetate is contraindicated in pregnancy (Category X). There is a high risk of fetal loss and congenital anomalies when administered during pregnancy, particularly during the first trimester due to suppression of pituitary gonadotropins and potential disruption of early embryonic development. In animal studies, leuprolide caused increased fetal mortality and teratogenicity across all trimesters. |
| Fetal Monitoring | Pregnancy testing must be performed prior to initiation of therapy to rule out pregnancy. If pregnancy is suspected during treatment, leuprolide should be discontinued immediately and the pregnancy evaluated. Ultrasound monitoring may be indicated to assess fetal viability and development if exposure occurs. |
| Fertility Effects | Leuprolide acetate suppresses pituitary gonadotropin secretion, leading to reversible inhibition of ovulation and spermatogenesis. Fertility is expected to return upon discontinuation of therapy, but the time to recovery may vary. In females, ovulation may resume after treatment ends; in males, testosterone levels and spermatogenesis typically recover within months. |
| Food/Dietary | No clinically significant food interactions established. Avoid grapefruit juice as it may alter hormone metabolism, though not specifically studied for leuprolide. Maintain adequate calcium and vitamin D intake (e.g., dairy, fortified foods, supplements) to counteract potential bone mineral density loss. |
| Clinical Pearls | Leuprolide acetate is a GnRH agonist that initially causes a surge in LH and FSH (flare effect) lasting 1-2 weeks, potentially worsening symptoms in hormone-sensitive cancers. Concomitant antiandrogen therapy (e.g., bicalutamide) may be required for prostate cancer to prevent flare. Depot formulations provide sustained release; ensure proper reconstitution and deep intramuscular or subcutaneous administration. Monitor serum testosterone in prostate cancer; castrate level <50 ng/dL is therapeutic goal. For central precocious puberty, monitor growth velocity, bone age, and pubertal development every 3-6 months. Injection site reactions are common; rotate sites. |
| Patient Advice | This medication causes a temporary increase in certain hormone levels during the first few weeks, which may worsen your symptoms; your doctor may prescribe additional medication to manage this. · For prostate cancer: you may experience hot flashes, decreased libido, erectile dysfunction, and loss of bone density. Report new bone pain or difficulty urinating immediately. · For endometriosis or uterine fibroids: you may have menstrual cessation and menopausal-like symptoms; these are reversible upon discontinuation. Use non-hormonal contraception as pregnancy is contraindicated. · Injections are typically given every 1, 3, 4, or 6 months depending on formulation. Do not miss appointments. Report signs of injection site infection (redness, swelling, warmth, drainage). · Avoid alcohol or hot beverages immediately after injection to reduce vasodilation and injection site discomfort. · Do not stop treatment abruptly; consult your healthcare provider before discontinuing. |