METHYLTESTOSTERONE (meth-ill-tess-toss'te-rone)
Android, Metandren , Testred, Virilon Classifications: hormone; androgen/anabolic steroid; Therapeutic: anabolic steroid Prototype: Testosterone Pregnancy Category: X Controlled Substance: Schedule III
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Availability
10 mg, 25 mg tablets
Action
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 Effect
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 (15 y postmenopausal), postpartum
breast engorgement.
Contraindications
Liver dysfunction; prostate cancer; severe cardiac, renal, or hepatic disease; pregnancy (category X), lactation.
Cautious Use
Mild or moderate liver, kidney, or cardiac dysfunction; heart failure, diabetes mellitus; prostatic hypertrophy.
Route & Dosage
Replacement Adult: PO 1050 mg/d in divided doses
Breast Cancer Adult: PO 50200 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 35 d
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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 from GI tract.
Metabolism: In liver.
Elimination: 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.