Classifications: antineoplastic aromatase inhibitor; Therapeutic: antineoplastic
Pregnancy Category: D
250 mg tablets
Blocks aromatase principally in the adrenal glands, thereby preventing conversion of androgens to estrogens in peripheral
tissues. Also blocks adrenal corticosteroid biosynthesis in the adrenal glands by inhibiting enzymatic conversion of cholesterol
to precursors of cortisol and aldosterone.
Because estrogens are supplied principally by the adrenal glands in postmenopausal and oophorectomized women, aminoglutethimide-induced
lowering of plasma estrogen levels (by adrenal suppression) is reportedly as effective as that produced by surgical adrenalectomy.
Temporary treatment of selected patients with Cushing's syndrome associated with adrenal carcinoma, ectopic ACTH-producing
tumors, or adrenal hyperplasia.
To produce medical adrenalectomy in postmenopausal women with a positive estrogen receptor test, metastatic breast cancer,
or who fail or relapse with tamoxifen, and for patients with prostatic carcinoma.
Hypothyroidism; infection. Safety during pregnancy (category D), lactation, and in children is not established.
Route & Dosage
Adult: PO 250 mg q6h, may be increased 250 mg/d q12wk if needed (max: 2 g/d)
Adult: PO 250 mg b.i.d. and hydrocortisone 60 mg h.s., 20 mg in a.m., and 20 mg at 2 p.m. daily for 2 wk, then 250 mg q.i.d. and hydrocortisone
20 mg h.s., 10 mg in a.m., and 10 mg at 2 p.m. thereafter
- Note: For breast cancer, 40 mg of hydrocortisone daily, in divided doses is usually ordered to be given concurrently.
- Store at 15°30° C (59°86° F) in tightly closed containers unless otherwise directed.
Adverse Effects (≥1%)CNS:
Lethargy, drowsiness, dizziness,
uncontrolled eye movements (dose related); clumsiness, headache. CV: Hypotension, tachycardia. Endocrine:
Nausea, vomiting, anorexia, hepatotoxicity. Hematologic:
decreased Hgb and Hct, anemia
, Coombs' negative hemolytic anemia
. Skin: Measles-like (morbilliform) rash,
decreases pharmacologic effects of aminoglutethimide; decreases anticoagulant response to warfarin.
35 d. Distribution:
Crosses placenta. Metabolism:
In liver. Elimination:
By kidneys; recovery of adrenal responsiveness to stress
occurs 3672 h after discontinuation. Half-Life:
13 h (7 h with long-term use).
Assessment & Drug Effects
- Monitor & report S&S of: Adrenal insufficiency or hypothyroidism (see Appendix F); in older adults, CNS effects (e.g., lethargy,
ataxia, orthostatic dizziness, lightheadedness).
- Lab tests: Baseline & periodic fasting plasma cortisol levels, periodic CBC with differential, serum electrolytes, serum
alkaline phosphate, liver functions, and thyroid function.
- Monitor BP in the recumbent and upright positions to evaluate fluid volume status and presence of orthostatic hypotension.
- Note: Dose reduction or temporary discontinuation may be indicated by: extreme drowsiness, severe skin rash, extremely low cortisol
- Note: Patients with Cushing's syndrome may show reduced effect with continuing therapy and generally are not treated beyond 3
mo with this drug.
Patient & Family Education
- Change positions gradually, pausing between each change. Do not stand still for prolonged periods.
- Note: Lethargy, drowsiness, dizziness, and other adverse effects often disappear during the first few weeks of therapy. Inform
physician if adverse effects persist or become bothersome.
- Report skin rash that persists beyond 58 d.
- Contact physician immediately in times of physical and emotional distress (e.g., acute illness, dental work). Steroid supplements
may be indicated.
- Do not drive or engage in potentially hazardous activities until response to drug is known.
- Carry medical identification indicating medical diagnosis, medication(s), physician's name, address, and telephone number.
- Notify physician immediately if pregnancy is suspected.