General
Woman 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. The patient and physician may decide that some virilization will be tolerated during treatment for breast carcinoma.
Priapism or excessive sexual stimulation may develop. Males, especially the elderly, may become overstimulated. In treating males for symptoms of climacteric, avoid stimulation to the point of increasing the nervous, mental, and physical activities beyond the patient’s cardiovascular capacity.
Oligospermia and reduced ejaculatory volume may occur after prolonged administration or excessive dosage.
Information for the Patients
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 hair on the face.
All Patients: Any nausea, vomiting, changes in skin color, or ankle swelling.
Any male adolescent patient receiving androgens for delayed puberty should have bone development checked every 6 months.
Laboratory Tests
- Women with disseminated breast carcinoma should have frequent determination of urine and serum calcium levels during the course of androgen therapy (see WARNINGS).
- Because of the hepatotoxicity associated with the use of 17-alpha-alkylated androgens, liver function tests should be obtained periodically.
- Periodic (every 6 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 hemotocrit should be checked periodically for polycythemia in patients who are receiving high doses of androgens.
Drug Interactions
1. Anticoagulants: C-17 substituted derivatives of testosterone, such as methandrostenolone have been reported to decrease the anticoagulant requirements
of patients receiving oral anticoagulants. Patients receiving anticoagulant therapy require close monitoring, especially when androgens are started or
stopped.
2. Oxyphenbutazone: Concurrent administration of oxyphenbutazone and androgens may result in elevated serum levels of oxyphenbutazone.
3. Insulin: In diabetic patients, metabolic effects of androgens may decrease blood glucose and insulin requirements.
Drug/Laboratory Test Interference
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, Mutagenesis, Impairment of Fertility
Animal Data: 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.
Human Data: 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 of developing prostatic hypertrophy and prostatic carcinoma although conclusive evidence to support this concept is lacking.
This compound has not been tested for mutagenic potential. However, as noted above, carcinogenic effects have been attributed to treatment with adrogenic hormones. The potential carcinogenic effects likely occur through a hormonal mechanism rather than by a direct chemical interaction mechanism.
Impairment of fertility was not tested directly in animal species. However, as noted below under ADVERSE REACTIONS, oligospermia in males and amenorrhea in females are potential adverse effects of treatment with METHITEST™ (methyltestosterone) tablets. Therefore, impairment of fertility is a possible outcome of treatment with METHITEST™ (methyltestosterone) tablets.
Pregnancy: Teratogenic Effects
Pregnancy Category X (see CONTRAINDICATIONS)
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 children 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 (see INDICATIONS & USAGE, and WARNINGS).