Nonsteroidal Antiandrogen
Nonsteroidal Antiandrogen
Action And Clinical Pharmacology: Flutamide demonstrates potent antiandrogenic effects by inhibiting androgen uptake and/or inhibiting nuclear binding of androgen in target tissues.
Indications And Clinical Uses: For use in combination with LHRH agonistic analogues (such as leuprolide acetate) for the treatment of metastatic prostatic carcinoma (Stage D2). To achieve the benefit of the adjunctive therapy with flutamide, treatment must be started simultaneously using both drugs. Also as an adjunctive therapy to orchiectomy, in order to achieve complete androgen blockade.
Precautions: Periodic liver function tests and sperm count determinations must be performed in patients on long-term treatment with flutamide.
Drug Interactions: Interactions between flutamide and leuprolide have not occurred. In patients receiving long-term warfarin therapy, increases in prothrombin time have been reported after flutamide monotherapy was initiated. Therefore, close monitoring of prothrombin time is recommended and adjustment of the anticoagulant dose may be necessary when flutamide is administered concomitantly with warfarin.
Information for the Patient: Patients should be informed that flutamide and the drug used for medical castration should be administered concomitantly, and that they should not interrupt their dosing or stop taking these medications without consulting their physician.
Adverse Reactions: The most frequently reported adverse reactions to flutamide monotherapy are gynecomastia and/or breast tenderness, sometimes accompanied by galactorrhea. These reactions disappear upon discontinuation of treatment or reduction in dosage.
Laboratory Values: Reported abnormal laboratory test results include elevated AST, ALT; elevated blood urea nitrogen (BUN) and bilirubin levels; less frequently, elevated serum creatinine levels and elevated gamma-glutamyl transferase levels have been reported.
Symptoms And Treatment Of Overdose: Symptoms and Treatment: In animal studies with flutamide alone, signs of overdose included hypoactivity, piloerection, slow respiration, ataxia, and/or lacrimation, anorexia, tranquillization, emesis and methemoglobinemia.
Dosage And Administration: The recommended dosage of flutamide in combination with orchiectomy or in combination with an LHRH agonist is one 250 mg tablet 3 times a day at 8-hour intervals. In combination with an LHRH agonist, either the 2 agents may be initiated simultaneously, or flutamide therapy may be started 24 hours prior to initiation of the LHRH agonist.
Availability And Storage: Each round, biconvex, pale yellow, compressed tablet, engraved with ‘EUFLEX’ on one face, and a single score on the other with the ‘SP’ logo engraved on each side of the score line, contains: flutamide 250 mg. Nonmedicinal ingredients: cellulose, lactose, magnesium stearate, pregelatinized starch, silica gel and sodium lauryl sulfate. Tartrazine-free. Bottles of 100. Store at 2 to 30°C.