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Medication Safety Issues
Sound-alike/look-alike issues:
Testolactone may be confused with testosterone
Pronunciation
(tes toe LAK tone)
U.S. Brand Names
Generic Available
No
Canadian Brand Names
Pharmacologic Category
Use: Labeled Indications
Palliative treatment of advanced or disseminated breast carcinoma
Restrictions
C-III
Pregnancy Risk Factor
C
Pregnancy Considerations
Teratogenic effects were not observed in animal studies. Testolactone should only be used in postmenopausal women; use during pregnancy is not recommended.
Lactation
Excretion in breast milk unknown/not recommended
Contraindications
Hypersensitivity to testolactone or any component of the formulation; treatment of breast cancer in men
Warnings/Precautions
Disease-related concerns:
• Cardiovascular disease: Use with caution in patients with cardiovascular disease.
• Diabetes: Use with caution in patients with diabetes mellitus; monitor carefully.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
• Porphyria: Use with caution in patients with a history of porphyria.
• Renal impairment: Use with caution in patients with renal impairment.
Special populations:
• Pediatrics: Safety and efficacy have not been established in children.
• Women: For use in postmenopausal women or in premenopausal women without ovarian function only.
Adverse Reactions
Frequency not defined.
Cardiovascular: Blood pressure increased, edema
Central nervous system: Malaise
Dermatologic: Alopecia (rare), maculopapular rash
Endocrine & metabolic: Hypercalcemia
Gastrointestinal: Anorexia, diarrhea, nausea, tongue edema
Neuromuscular & skeletal: Paresthesia, peripheral neuropathy
Miscellaneous: Nail growth disturbance (rare)
Drug Interactions
CycloSPORINE: Androgens may enhance the hepatotoxic effect of CycloSPORINE. Androgens may increase the serum concentration of CycloSPORINE. Risk D: Consider therapy modification
Vitamin K Antagonists (eg, warfarin): Androgens may enhance the anticoagulant effect of Vitamin K Antagonists. Risk D: Consider therapy modification
Mechanism of Action
Testolactone is a synthetic testosterone derivative without significant androgen activity. The drug inhibits steroid aromatase activity, thereby blocking the production of estradiol and estrone from androgen precursors such as testosterone and androstenedione. Unfortunately, the enzymatic block provided by testolactone is transient and is usually limited to a period of 3 months.
Pharmacodynamics/Kinetics
Absorption: Well absorbed
Metabolism: Hepatic (forms metabolites)
Excretion: Urine
Dosage
Adults: Females: Oral: 250 mg 4 times/day for at least 3 months; desired response may take as long as 3 months
Monitoring Parameters
Plasma calcium levels
Test Interactions
Plasma estradiol concentrations by RIA
Patient Education
Take as directed; do not discontinue without consulting prescriber. Effectiveness of therapy may take several months. Maintain adequate hydration (2-3 L/day of fluids) unless instructed to restrict fluid intake, and diet and exercise program recommended by prescriber. You may experience nausea or vomiting (small, frequent meals, frequent mouth care, sucking lozenges, or chewing gum may help). Report fluid retention (swelling of ankles, feet, or hands; respiratory difficulty or sudden weight gain); numbness, tingling, or swelling of fingers, toes, or face; skin rash, redness, or irritation; or other adverse reactions. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Breast-feeding is not recommended.
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Tongue edema.
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
None reported
Mental Health: Effects on Psychiatric Treatment
None reported
Nursing: Physical Assessment/Monitoring
For use in postmenopausal women or in premenopausal women without ovarian function only. May increase effects of oral anticoagulants. Evaluate effectiveness of therapy, laboratory tests, and adverse reactions. Assess knowledge/teach patient appropriate use, possible side effects/appropriate interventions, and adverse symptoms to report.
Oncology: Emetic Potential
Very low (<10%)
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Tablet:
Teslac®: 50 mg [DSC]
International Brand Names
Lexi-Comp.com
Last full review/revision January 2009
Content last modified January 2009
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