flutamide

flutamide /flu·ta·mide/ (floo´tah-mid) a nonsteroidal antiandrogen, used in the treatment of metastatic prostatic carcinoma.

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flutamide

(floo´tmīd´),
n brand name: Eulexin;
drug class: antineoplastic;
action: interferes with testosterone at cellular level, inhibits androgen uptake;
uses: metastatic prostatic carcinoma, stage D2 in combination with LHRH agonistic analogs (leuprolide).

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flutamide

a nonsteroidal drug with antiandrogen effects; used in the treatment of prostatic hyperplasia in dogs.

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flutamide Warning - Hazardous drug!

Chimax (UK), Drogenil (UK), Euflex (CA), Novo-Flutamide (CA)

Pharmacologic class: Antiandrogen

Therapeutic class: Antineoplastic

Pregnancy risk category D

FDA Boxed Warning

• Postmarketing hospitalizations and deaths from hepatic failure have occurred. Evidence of hepatic injury includes elevated serum transaminase levels, jaundice, hepatic encephalopathy, and death related to acute hepatic failure. In some patients, hepatic injury reversed after drug withdrawal. Approximately half of reported cases occurred within first 3 months of therapy.
• Measure serum transaminase levels before therapy begins. Drug isn't recommended if alanine aminotransferase (ALT) values exceed twice the upper limit of normal (ULN). Once therapy begins, measure transaminase levels monthly for first 4 months and periodically thereafter. Obtain liver function tests at first sign of hepatic dysfunction. If patient has jaundice or ALT level exceeding 2 x ULN, discontinue drug immediately and follow liver function tests closely until they resolve.

Action

Exerts potent antiandrogenic activity at cellular level by inhibiting androgen uptake or nuclear binding of androgen

Availability

Capsules: 125 mg

⊘Indications and dosages

➣ Metastatic prostate cancer

Adults: 250 mg P.O. t.i.d. q 8 hours, given with luteinizing hormone-releasing hormone (LHRH) analog. Total daily dosage is 750 mg.

Off-label uses

• Benign prostatic hypertrophy

Contraindications

• Hypersensitivity to drug
• Severe hepatic impairment
• Sleep apnea
• Women

Precautions

None

Administration

• Be aware that leuprolide acetate is the most common LHRH analog given with flutamide.

Route	Onset	Peak	Duration
P.O.	Variable	2 hr	72 hr

Adverse reactions

CNS: drowsiness, confusion, depression, anxiety, nervousness, paresthesia

CV: peripheral edema, hypertension

GI: nausea, vomiting, diarrhea, constipation, abdominal pain, dyspepsia, anorexia, dry mouth

GU: erectile dysfunction, loss of libido, gynecomastia, hot flashes

Hematologic: anemia, leukopenia, thrombocytopenia

Hepatic: hepatitis

Skin: rash, photosensitivity

Interactions

Drug-drug . Warfarin: increased prothrombin time

Drug-diagnostic tests. Alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatine kinase: increased levels

Hemoglobin, platelets, white blood cells: decreased levels

Drug-herbs. Chaparral, comfrey, eucalyptus, germander, pennyroyal, skullcap, valerian: increased risk of hepatotoxicity

Drug-behaviors. Sun exposure: increased risk of photosensitivity

Patient monitoring

• Monitor CBC and liver function tests.
☞ Watch for bleeding tendency and signs and symptoms of hepatic damage (jaundice, vomiting, dark yellow or brown urine).
• Monitor blood pressure.

Patient teaching

☞ Instruct patient to immediately report unusual bleeding or bruising.
• Tell patient to avoid activities that can cause injury. Advise him to use soft toothbrush and electric razor to avoid gum and skin injury.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• Instruct patient to minimize GI upset by eating frequent, small servings of healthy food.
• Tell patient he'll undergo regular blood testing during therapy.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.

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flutamide Endocrinology A nonsteroidal antiandrogen which, unlike steroidal antiandrogens, lacks androgenic, estrogenic, antiestrogenic, progestational, adrenocortical, and antigonadotropic activity; flutamide has been used for metastatic androgen-responsive prostate CA and, when combined with LHRH analogues, achieves a relatively complete androgen blockade; flutamide has been used to treat acne and hirsutism Adverse effects GI tract–diarrhea, nausea, dizziness, gynecomastia, hepatic dysfunction or toxicity. Cf Nilutamide.