Methyltestosterone

Breast cancer, metastatic (females): Oral: 50 to 200 mg daily.

Delayed puberty (males): Oral: 10 to 50 mg daily; limit treatment duration to 4 to 6 months; use lower range of dosing and individualize dose based on response and tolerability.

Contraindications:

Men with breast cancer or with known or suspected prostate cancer; women who are or may become pregnant.

Documentation of allergenic cross-reactivity for androgens is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Interactions:

Agents with Blood Glucose Lowering Effects: Androgens may enhance the hypoglycemic effect of Agents with Blood Glucose Lowering Effects. Risk C: Monitor therapy

CycloSPORINE (Systemic): Androgens may enhance the hepatotoxic effect of CycloSPORINE (Systemic). Androgens may increase the serum concentration of CycloSPORINE (Systemic). Management: Consider avoiding concomitant use of androgens and cyclosporine. If concomitant use is unavoidable, monitor serum cyclosporine concentrations and for signs and symptoms of hepatotoxicity. Cyclosporine dose reductions may be required. Risk D: Consider therapy modification

Vitamin K Antagonists (eg, warfarin): Androgens may enhance the anticoagulant effect of Vitamin K Antagonists. Management: Monitor for increased effects of vitamin K antagonists if an androgen is initiated/dose increased, or decreased effects if androgen is discontinued/dose decreased. Significant reductions in vitamin K antagonist dose are likely required. Risk D: Consider therapy modification

Pregnancy and Lactation:

Use is contraindicated in women who are pregnant. Exposure during pregnancy may cause virilization of the external genitalis of the female fetus, including clitoromegaly, abnormal vaginal development, and fusion of genital folds to form a scrotal-like structure. The degree of masculinization is dose related and most likely to occur when androgens are administered in the first trimester. If a patient becomes pregnant while taking androgens, she should be counseled on the potential hazard to the fetus.

It is not known if methyltestosterone is excreted in breast milk. Due to the potential for serious adverse reactions in the nursing infant, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of treatment to the mother.

Warning and Precaution:

• Cardiovascular events: Available studies are inconclusive regarding the risk of developing major adverse cardiovascular events such as nonfatal myocardial infarction, stroke, or cardiovascular death following testosterone use; most data are specific to men who were prescribed testosterone therapy. Evaluate patients for cardiovascular risk factors prior to initiating therapy and monitor closely during therapy for cardiovascular events.
• Hepatic effects: Prolonged use and/or high doses may cause peliosis hepatis, hepatic neoplasms including hepatocellular carcinoma, cholestatic hepatitis, and jaundice. Discontinue if cholestatic hepatitis with jaundice or abnormal liver function tests occur.
• Oligospermia: May cause oligospermia and reduced ejaculatory volume after prolonged administration or excessive dosage.
• Polycythemia: May increase hematocrit requiring dose adjustment or discontinuation. Withhold initial treatment in patients with hematocrit >48% or >50% if living at higher altitudes. Discontinue therapy if hematocrit exceeds 54%
• Priapism: Priapism or excessive sexual stimulation may occur.
• Venous thromboembolism: Venous thromboembolic events, including deep vein thrombosis (DVT) and pulmonary embolism (PE), have been reported with testosterone products. Evaluate patients with symptoms of pain, edema, warmth, and erythema in the lower extremity for DVT and those with acute shortness of breath for PE. Discontinue therapy if a venous thromboembolism is suspected. Use in patients with thrombophilia is not recommended

Adverse Reactions:

Cardiovascular: Edema

Central nervous system: Anxiety, depression, headache, paresthesia

Dermatologic: Acne vulgaris, androgenetic alopecia

Endocrine & metabolic: Change in libido, gynecomastia (males), hirsutism (females), hypercalcemia, hypercholesterolemia, menstrual disease (includes amenorrhea)

Gastrointestinal: Nausea, vomiting

Genitourinary: Benign prostatic hypertrophy (males), impotence (males), mastalgia (females), oligospermia (males; at high doses), priapism (males), testicular atrophy (males), virilization (males and females)

Hematologic & oncologic: Clotting factors suppression, polycythemia, prostate carcinoma (males)

Hepatic: Abnormal liver function tests, cholestatic hepatitis, hepatic insufficiency, hepatic necrosis, jaundice, peliosis hepatitis

Storage:

Store below 30 and protect from light and moisture.