Flutamide

Introduction: Flutamide is used in the treatment of cancer of the prostate gland. It works by blocking the effects of male hormones such as testosterone.

How it works: Flutamide is a nonsteroidal 'pure' antiandrogen which acts directly on the target tissues either by blocking androgen uptake or by inhibiting cytoplasmic and nuclear binding of androgen.

Important Information: It is used in combination with LHRH agonists or orchiectomy. Periodic liver function tests and sperm count determinations must be performed during treatment.

• Metastatic prostatic carcinoma (Stage D2) - in combination with LHRH agonist
• Adjunctive therapy to orchiectomy
• Bulky locally advanced Stage B2 and Stage C prostatic carcinoma - prior to and during external beam radiotherapy

Hormonal Chemotherapy

Nonsteroidal antiandrogen

In animal studies, flutamide demonstrates potent antiandrogenic effects. It exerts its antiandrogenic action by inhibiting androgen uptake and/or by inhibiting nuclear binding of androgen in target tissues or both. Prostatic carcinoma is known to be androgen-sensitive and responds to treatment that counteracts the effect of androgen and/or removes the source of androgen.

Flutamide blocks androgen receptors to prevent the effects of testosterone and DHT, resulting in reduced prostate cancer cell growth.

Adult Dose:

• In combination with orchiectomy or LHRH agonist: 250 mg tablet three times a day at eight-hour intervals.
• Stage B2 and C prostatic carcinoma: 250 mg three times a day at eight-hour intervals. Start 8 weeks prior to radiation therapy and continue through the course.

* Use as directed by the registered physician

Oral tablet. Can be taken with or without food, preferably at the same time every day. Swallow whole, do not chew or crush.

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and follow your regular schedule.

Common Side Effects:

• Breast enlargement in males - 9%
• Nausea/Vomiting - 11%
• Diarrhea - 12%
• Anorexia - 4%
• CNS reactions (drowsiness/confusion/depression/anxiety) - 1%
• Anemia - 6%
• Leukopenia - 3%
• Thrombocytopenia - 1%
• Hypertension - 1%

Serious Side Effects: Hepatic injury (hepatitis, jaundice, hepatic necrosis) - <1%.

Precautions:

• Periodic liver function tests and sperm count determinations must be performed on long-term treatment.
• Inform doctor if you develop signs of liver injury (pruritus, dark urine, persistent anorexia, jaundice, right upper quadrant tenderness or unexplained flu-like symptoms).
• Use with caution in cardiac disease (may cause fluid retention).
• Avoid during pregnancy and lactation.

Contraindications:

• Hypersensitivity to flutamide
• Severe hepatic impairment
• Pregnancy and lactation

Drug Interactions:

• Increased prothrombin time with warfarin.
• Increased theophylline plasma concentrations.

Food Interactions:

• Unsafe to consume alcohol with Flutamide.

Use in Pregnancy: Unsafe during pregnancy. There is definite evidence of risk to the developing baby.

Use in Lactation: Information regarding the use of Flutamide during breastfeeding is not available. Please consult your doctor.

Pediatric Use: Flutamide is not indicated for women and not recommended for children.

Geriatric Use: No specific dosage adjustment is necessary for elderly patients. Use with caution.

Renal Impairment: Probably safe in kidney disease. Dose adjustment may not be needed.

Hepatic Impairment: Unsafe in liver disease and should be avoided.

Overdose: Limited information available on overdose. Employ usual supportive measures.

Storage: Keep below 30°C, away from light and moisture. Keep out of reach of children.

Flutamide Tablet