Definition
Aminoglutethimide, also known by the brand name Cytadren, is a cancer drug which inhibits the formation of hormones like adrenal glucocorticoids, mineralocorticoids, estrogen, androgens, and aldosterone.
Purpose
Aminoglutethimide is used to treat Cushing's disease, breast cancer, or prostate cancer. It blocks the conversion of cholesterol to delta-5-pregnenolone, a precursor for the formation of the corticosteroids.
Description
Aminoglutethimide is used clinically to reduce the amount of the hormones that can sometimes cause tumors to grow more quickly or are necessary for the survival of the tumor. For example, estrogen is important for the growth of some breast tumors. Lowering estrogen production by the administration of aminoglutethimide might reduce tumor growth or contribute to the destruction of the tumor.
Recommended Dosage
Aminoglutethimide is given orally and dosages vary from patient to patient based on a number of factors, including the underlying disease process.
Precautions
Because some corticosteroid is necessary for normal function, patients should receive steroid replacement in addition to aminoglutethimide. Patients may require more corticosteroid when undergoing surgery, illness, or other conditions that cause stress. Hormones that affect the balance of sodium in the body may also be affected by aminoglutethimide and might have to be replaced as a result. If they are not replaced, patients may experience constant low blood pressure or low blood pressure upon standing.
Pregnant women should be warned that aminoglutethimide administration could cause fetal abnormalities. Pregnant patients should consult their physician about the current state of knowledge regarding risks and alternatives before beginning administration of aminoglutethimide. Female patients of childbearing age should attempt to avoid pregnancy while taking this drug. Mothers who are nursing should discontinue nursing while taking this drug.
Side Effects
Common side effects from the administration of aminoglutethimide is rash (possibly associated with fever) which usually occurs in the first two weeks of therapy. It is usually self-limiting and gets better in a about a week. If the rash continues after one week patient should contact his/her physician or nurse. Fatigue is another common side effect of the drug and usually occurs in the first week of therapy. It may take about a month before it gets better. It can be very severe in some patients and if this is the case the patient's physician or nurse should be notified. Female patients may experience masculinization: new and excessive hair growth, a deeper voice, and irregular, abnormal, or absent menstrual periods. Thyroid function may be decreased after several weeks of therapy and the patient's thyroid should be monitored by the physician. Mild nausea and vomiting may also occur, as well as dizziness, depression, shaking, difficulty speaking, and increased heart rate. Any of these effects, or other unusual symptoms, should be reported to the patient's physician.
Interactions
Dexamethasone, blood-thinning medications, theophylline, and digoxin doses for patients taking aminoglutethimide may need to be increased by the physician. Patients should tell their doctors if they have a known allergic reaction to aminoglutethimide medications or substances, such as foods and preservatives. Before taking any new medications, including nonprescription medications, vitamins, and herbal medications, patients should notify their doctors.
—Michael Zuck, Ph.D.
