flutamide

General

High Alert Medication: This medication bears a heightened risk of causing significant patient harm when it is used in error.

Pronunciation:
floo-ta-mide

Trade Name(s)

• Eulexin

Ther. Class.

antineoplastics

Pharm. Class.

antiandrogens

Indications

Prostate cancer (in combination with a luteinizing hormone-releasing hormone [LHRH] agonist).

Action

Antagonizes the effects of androgen (testosterone) at the cellular level.

Therapeutic Effect(s):

Decreased growth of prostate carcinoma, an androgen-sensitive tumor.

Pharmacokinetics

Absorption: Well absorbed after oral administration.

Distribution: Unknown.

Metabolism and Excretion: Mostly metabolized by the liver. Some conversion to another antiandrogenic compound (2-hydroxyflutamide).

Half-life: Unknown.

TIME/ACTION PROFILE

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity;
• Black Box:  Severe hepatic impairment.

Use Cautiously in:

Severe cardiovascular disease.

Adverse Reactions/Side Effects

Side effects primarily caused by LHRH antagonist

CV: edema, hypertension

Derm: photosensitivity, rash

Endo: gynecomastia, hot flushes

GI: diarrhea, nausea, vomiting, hepatotoxicity

GU: erectile dysfunction, loss of libido

Neuro: anxiety, confusion, drowsiness, mental depression, nervousness

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

None reported.

Route/Dosage

PO (Adults): 250 mg every 8 hr.

Availability

Capsules: 125 mg, 250 mg 

Assessment

• Monitor for diarrhea, nausea, and vomiting. Adjust diet as tolerated. Notify health care provider if these symptoms become severe.

Lab Test Considerations:

May ↑ AST, ALT, bilirubin, and serum creatinine. Monitor ALT before therapy, monthly for the 1st 4 mo of therapy, and periodically thereafter. Liver function tests should also be obtained at the 1st sign of nausea, vomiting, abdominal pain, fatigue, anorexia, or hyperbilirubinemia. If ALT ↑ above 2 times the upper limit of normal or if patient develops jaundice, immediately discontinue flutamide.

• May ↑ plasma estradiol and testosterone concentrations.

Implementation

• Used in combination with LHRH agonist, such as leuprolide.
• PO Administer capsules three times a day, 8 hr apart.

Patient/Family Teaching

• Explain that flutamide must be taken in conjunction with leuprolide. Instruct patient to take flutamide exactly as directed. If a dose is missed, take as soon as possible unless almost time for next dose. Do not double doses.
• Warn patient that side effects such as hot flashes, loss of sex drive, erectile dysfunction, and breast enlargement may be caused by the LHRH agonist. The primary side effect of flutamide alone is diarrhea, but the combination of drugs is necessary to achieve the therapeutic effect.
• Advise patient to notify health care provider immediately if dark urine, itching, loss of appetite, nausea, vomiting, pain in right side, or yellow eyes or skin occurs. Hepatotoxicity usually resolves when flutamide is discontinued, but it may be progressive and fatal; requires immediate medical attention.

Evaluation/Desired Outcomes

Decrease in the spread of prostate cancer.