Testosterone Enanthate
Cas No 315-37-7


Precautions

General

Women should be observed for signs of virilization (deepening of the voice, hirsutism, acne, clitoromegaly, and menstrual irregularities). Discontinuation of drug therapy at the time of evidence of mild virilism is necessary to prevent irreversible virilization. Such virilization is usual following androgen use at high doses and is not prevented by concomitant use of estrogens. A decision may be made by the patient and the physician that some virilization will be tolerated during treatment for breast carcinoma.

Because androgens may alter serum cholesterol concentration, caution should be used when administering these drugs to patients with a history of myocardial infarction or coronary artery disease. Serial determinations of serum cholesterol should be made and therapy adjusted accordingly. A causal relationship between myocardial infarction and hypercholesterolemia has not been established.

Information for Patients

Male adolescent patients receiving androgens for delayed puberty should have bone development checked every six months.

The physician should instruct patients to report any of the following side effects of androgens:

Adult or adolescent males - too frequent or persistent erections of the penis.

Women - hoarseness, acne, changes in menstrual periods, or more facial hair.

All patients - any nausea, vomiting, changes in skin color, or ankle swelling.

Geriatric Use

Clinical studies of Testosterone Enanthate injection, USP did not include sufficient numbers of subjects, aged 65 and older, to determine whether they respond differently from younger subjects. Testosterone replacement is not indicated in geriatric patients who have age-related hypogonadism only ("andropause"), because there is insufficient safety and efficacy information to support such use. Current studies do not assess whether testosterone use increases risks of prostate cancer, prostate hyperplasia, and cardiovascular disease in the geriatric population.

Laboratory Tests
Women with disseminated breast carcinoma should have frequent determination of urine and serum calcium levels during the course of androgen therapy.

Periodic (every six months) X-ray examinations of bone age should be made during treatment of prepubertal males to determine the rate of bone maturation and the effects of androgen therapy on the epiphyseal centers.

Hemoglobin and hematocrit should be checked periodically for polycythemia in patients who are receiving high doses of androgens.

Drug Interactions
When administered concurrently, the following drugs may interact with androgens:

Anticoagulants, oral - C-17 substituted derivatives of testosterone, such as methandrostenolone, have been reported to decrease the anticoagulant requirement. Patients receiving oral anticoagulant therapy require close monitoring especially when androgens are started or stopped.

Antidiabetic drugs and insulin - In diabetic patients, the metabolic effects of androgens may decrease blood glucose and insulin requirements.

ACTH and corticosteroids - Enhanced tendency toward edema. Use caution when giving these drugs together, especially in patients with hepatic or cardiac disease.

Oxphenbutazone - Elevated serum levels of oxyphenbutazone may result.

Drug/Laboratory Test Interferences

Androgens may decrease levels of thyroxine-binding globulin, resulting in decreased total T4 serum levels and increased resin uptake of T3 and T4. Free thyroid hormone levels remain unchanged, however, and there is no clinical evidence of thyroid dysfunction.

Carcinogenesis

Testosterone has been tested by subcutaneous injection and implantation in mice and rats. The implant induced cervical-uterine tumors in mice, which metastasized in some cases. There is suggestive evidence that injection of testosterone into some strains of female mice increases their susceptibility to hepatoma. Testosterone is also known to increase the number of tumors and decrease the degree of differentiation of chemically induced carcinomas of the liver in rats.

There are rare reports of hepatocellular carcinoma in patients receiving long-term therapy with androgens in high doses. Withdrawal of the drugs did not lead to regression of the tumors in all cases.

Geriatric patients treated with androgens may be at an increased risk for the development of prostatic hypertrophy and prostatic carcinoma.

Nursing Mothers

It is not known whether androgens are excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from androgens, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

Androgen therapy should be used very cautiously in pediatric patients and only by specialists who are aware of the adverse effects on bone maturation. Skeletal maturation must be monitored every six months by an X-ray of the hand and wrist