METHYLTESTOSTERONE
(meth-ill-tess-toss'te-rone)
Android, Metandren

, Testred, Virilon
Classifications: hormones and synthetic substitutes; androgen/anabolic steroid
Prototype: Testosterone
Pregnancy Category: X
Controlled Substance: Schedule III

Availability

10 mg, 25 mg tablets; 10 mg buccal tablet

Actions

Short-acting steroid with androgen/anabolic activity ratio (1:1) similar to that of testosterone but less effective than its esters. Fails to produce full sexual maturation when administered to preadolescent male with complete testicular failure unless preceded by testosterone therapy.

Therapeutic Effects

Androgen activity is similar to testosterone; used in replacement therapy, and palliative treatment of postmenopausal female breast cancer.

Uses

Androgen replacement therapy, delayed puberty (male), palliation of female mammary cancer (1–5 y postmenopausal), postpartum breast engorgement.

Contraindications

Liver dysfunction; prostate cancer; pregnancy (category X), lactation.

Cautious Use

Liver, kidney, or cardiac dysfunction.

Route & Dosage

Replacement
Adult: PO 10–50 mg/d in divided doses

Breast Cancer
Adult: PO 50–200 mg/d in divided doses for duration of therapeutic response or no longer than 3 mo if no remission

Postpartum Breast Engorgement
Adult: PO 80 mg/d for 3–5 d

Administration

Oral

Place buccal tablets between cheek and gum. Ensure that tablet is absorbed, not chewed or swallowed; and eating or drinking avoided until absorption is complete.
Store at 15°–30° C (59°–86° F). Avoid freezing.

Adverse Effects (1%)

GI: Cholestatic hepatitis with jaundice, irritation of oral mucosa with buccal administration. Urogenital: Renal calculi (especially in immobilized patient), priapism. Endocrine: Acne, gynecomastia, edema, oligospermia, menstrual irregularities.

Interactions

Drug: Increases risk of bleeding associated with oral anticoagulants; possibly increases risk of cyclosporine toxicity; may decrease glucose level, making adjustment of doses of insulin, sulfonylureas necessary. Herbal: Echinacea may increase risk of hepatotoxicity.

Pharmacokinetics

Absorption: Readily absorbed from GI tract. Metabolism: Metabolized in liver. Elimination: Excreted in urine.

Nursing Implications

Assessment & Drug Effects

Lab tests: Monitor liver function periodically; report signs of hepatic toxicity (see Appendix F).
Monitor for flank pain, abdominal pain radiating to groin, or other symptoms of renal calculi.

Patient & Family Education

Be prepared for distressing and undesirable adverse effects of virilization (women) since dosage sufficient to produce remission in breast cancer is quantitatively similar to that used for androgen replacement in the male.
Report signs of virilism promptly. Voice change and hirsutism may be irreversible, even after drug is withdrawn.
Report priapism (men) or other signs of excess sexual stimulation. The physician will terminate therapy.
Report symptoms of jaundice with or without pruritus to physician; appears to be dose related. If liver function tests are altered at the same time, this drug will be withdrawn.
Do not breast feed while taking this drug.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug