TESTOSTERONE PROPIONATE
Clinical safety rating: avoid
Corticosteroids may increase edema risk and anticoagulants may have increased effects Can cause polycythemia and increased risk of cardiovascular events.
Testosterone propionate is a short-acting androgen receptor agonist. It binds to androgen receptors, leading to activation of androgen-responsive genes and promotion of male secondary sexual characteristics, anabolic effects, and erythropoiesis.
| Metabolism | Testosterone propionate is hydrolyzed to testosterone by esterases. Testosterone is metabolized primarily in the liver via CYP3A4 and 5α-reductase to dihydrotestosterone (DHT) and other metabolites, which undergo further conjugation and renal excretion. |
| Excretion | Renal: 90% (as glucuronide and sulfate conjugates); Fecal/Biliary: 10%. |
| Half-life | Terminal half-life: 0.8–1.2 hours (rapid elimination due to short ester chain; requires frequent dosing). |
| Protein binding | 97-99% bound primarily to sex hormone-binding globulin (SHBG) and albumin. |
| Volume of Distribution | 0.6–0.8 L/kg (distributes widely into tissues; low Vd reflects high protein binding). |
| Bioavailability | Intramuscular: 100% (by injection); Oral: <5% (extensive first-pass metabolism; not used orally). |
| Onset of Action | Intramuscular: 24-48 hours; Subcutaneous: 24-48 hours; Transdermal: not applicable for propionate. |
| Duration of Action | Intramuscular: 2-3 days (short-acting; requires injection every 2-3 days for sustained effects). |
| Molecular Weight | 344.49 |
50-400 mg intramuscularly every 2-4 weeks. For androgen replacement, 50-100 mg IM every 2 weeks.
| Dosage form | INJECTABLE |
| Renal impairment | GFR > 50 mL/min: no adjustment; GFR 10-50 mL/min: consider dose reduction by 25-50% due to accumulation; GFR < 10 mL/min: avoid use or use with extreme caution, monitoring for fluid retention and hypertension. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% and monitor liver function; Child-Pugh C: contraindicated due to risk of hepatotoxicity and fluid retention. |
| Pediatric use | Not recommended for pediatric use in growth or development. For delayed puberty, 25-50 mg IM every 2-4 weeks for 4-6 months; individualize based on response. Weight-based dosing: 2-5 mg/kg IM every 2-4 weeks (use with caution). |
| Geriatric use | Initiate at low end of dosing range (e.g., 25-50 mg IM every 2-4 weeks) due to increased risk of prostatic hyperplasia, cardiovascular events, and fluid retention. Monitor serum testosterone levels, hematocrit, and prostate-specific antigen (PSA) periodically. |
| 1st trimester | Androgens are contraindicated in pregnancy; testosterone propionate can cause virilization of female fetus and should be avoided during first trimester. |
| 2nd trimester | Continued risk of virilization; avoid use during second trimester due to potential adverse effects on fetal development. |
| 3rd trimester | Avoid use in third trimester; may cause virilization of female fetus and other androgen-related effects. |
Clinical note
Corticosteroids may increase edema risk and anticoagulants may have increased effects Can cause polycythemia and increased risk of cardiovascular events.
| FDA category | Contraindicated |
| Placental transfer | Testosterone propionate crosses the placenta; transfer to fetal circulation is documented, with potential for virilization of female fetus. |
■ FDA Black Box Warning
WARNING: VIRILIZATION IN WOMEN AND PRECOCIOUS PUBERTY IN CHILDREN. Prolonged use in women may cause hirsutism, voice deepening, and clitoral enlargement; in children, it may cause premature epiphyseal closure and precocious sexual development. Testosterone propionate should not be used in women of childbearing potential unless the benefit clearly outweighs the risk of virilization.
| Common Effects | Acne |
| Serious Effects |
PregnancyKnown hypersensitivity to testosterone propionate or any componentSerious cardiac, hepatic, or renal diseaseHypercalcemiaBreast cancer in malesProstate cancer
| Precautions | Risk of erythrocytosis and increased hematocrit; monitor hemoglobin/hematocrit periodically., May worsen sleep apnea, especially in patients with obesity or chronic lung disease., May cause fluid retention and exacerbate heart failure, hypertension, or renal disease., Can accelerate growth of androgen-sensitive prostate cancer and benign prostatic hyperplasia; monitor prostate-specific antigen (PSA)., May cause gynecomastia, oligospermia, and reduced fertility in males., Risk of hepatotoxicity with oral methyltestosterone, but less concern with injectable testosterone propionate; still monitor liver function., May affect bone growth in children; use with caution in pediatric patients., May cause psychiatric effects such as libido changes, depression, or aggression. |
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| Breastfeeding |
| Testosterone propionate is present in breast milk; may cause masculinization of female infants and adverse effects on lactation. Use only if clearly needed and with caution. |
| Lactation Rating | L4 (Possibly Hazardous) |
| Teratogenic Risk | Contraindicated in pregnancy. Testosterone propionate is an androgen; exposure during the first trimester can cause virilization of the female fetus (clitoromegaly, labial fusion). During second and third trimesters, continued virilization risk. Not recommended at any stage. |
| Fetal Monitoring | If accidental exposure during pregnancy, monitor fetal development with ultrasound for ambiguous genitalia. Maternal monitoring: signs of virilization, hirsutism, acne, voice changes, liver function tests, lipid profile, and blood pressure. |
| Fertility Effects | Testosterone propionate suppresses gonadotropin secretion, leading to oligospermia or azoospermia in males, and anovulation, menstrual irregularities, and reduced fertility in females. Effects may be reversible upon discontinuation. |
| Food/Dietary | No significant food interactions. Avoid alcohol as it may reduce testosterone production. |
| Clinical Pearls | Short-acting testosterone ester requiring IM injection every 2-3 days due to rapid absorption. Monitor serum testosterone levels midway between injections. Use with caution in patients with sleep apnea, severe heart failure, or history of polycythemia (hematocrit >54%). Contraindicated in men with breast or prostate cancer. Can cause erythrocytosis; check CBC at baseline and periodically. Avoid in patients with severe lower urinary tract symptoms due to risk of worsening BPH. May increase risk of venous thromboembolism. Use with aromatase inhibitor if gynecomastia develops. |
| Patient Advice | Inject deep intramuscularly, typically into the gluteal muscle, every 2 to 3 days as prescribed. · Rotate injection sites to reduce pain and lipodystrophy. · Report any new or worsening swelling in the legs, difficulty breathing, or signs of blood clots (pain, warmth, redness). · Notify your doctor if you develop breast tenderness, enlarged breasts, or persistent erections. · Do not use this medication if you have or have had prostate or breast cancer. · Regular blood tests are required to monitor testosterone levels and blood count. · Keep out of reach of children. Store at room temperature away from light. |