Eulexin (flutamide) is a nonsteroidal antiandrogen agent indicated for use in combination therapy with a luteinizing hormone-releasing hormone (LHRH) agonist for the management of metastatic prostate carcinoma (stage D2). By competitively blocking androgen receptors at the target tissue level, it inhibits the growth-stimulating effects of testosterone and dihydrotestosterone on prostatic carcinoma cells. This oral medication represents a critical component in combined androgen blockade strategies, offering a targeted mechanism to suppress tumor progression and disease-related symptoms in appropriate patient populations. Its well-established pharmacokinetic profile allows for consistent therapeutic levels when administered as prescribed under specialist supervision.

Features

• Active pharmaceutical ingredient: Flutamide 125 mg
• Pharmaceutical form: Film-coated tablets
• Mechanism: Nonsteroidal selective antiandrogen
• Administration: Oral route
• Bioavailability: Rapid and complete absorption
• Metabolism: Hepatic, to active hydroxylated derivatives
• Excretion: Primarily renal
• Half-life: Approximately 5-6 hours (flutamide); 8-10 hours (active metabolite)
• Special packaging: Blister packs with moisture barrier protection

Benefits

• Effectively suppresses androgen receptor signaling in prostate tissue
• Delays disease progression in metastatic prostate cancer
• Redces tumor-related pain and urinary obstruction symptoms
• Works synergistically with LHRH agonists for complete androgen blockade
• Maintains quality of life by controlling cancer-related symptoms
• Established safety profile with decades of clinical use

Common use

Eulexin is specifically indicated for use in combination with an LHRH agonist (such as leuprolide or goserelin) for the treatment of metastatic prostate carcinoma. This combination therapy approach provides complete androgen blockade by simultaneously suppressing testicular androgen production (via LHRH agonist) and blocking androgen receptor binding at the cellular level. The medication is typically initiated concurrently with LHRH agonist therapy and continued throughout treatment duration unless unacceptable toxicity occurs or disease progression warrants alternative approaches. Clinical studies have demonstrated improved progression-free survival and overall response rates with combined androgen blockade compared to monotherapy in appropriately selected patients.

Dosage and direction

The recommended adult dosage is one 125 mg tablet administered orally three times daily at approximately 8-hour intervals (total daily dose: 375 mg). Administration with food is acceptable as it does not significantly affect bioavailability. Tablets should be swallowed whole with water and not crushed or chewed. Treatment should be initiated concurrently with LHRH agonist therapy and generally continued until disease progression becomes evident. Dosage adjustment may be necessary in patients with hepatic impairment, though specific guidelines should be determined by the treating oncologist based on liver function tests and clinical status. No dosage adjustment is typically required for renal impairment.

Precautions

Regular monitoring of liver function tests (ALT, AST, bilirubin) is mandatory, particularly during the first four months of therapy, as hepatocellular toxicity may occur. Patients should be advised to report promptly any symptoms suggestive of liver dysfunction, including nausea, vomiting, abdominal pain, fatigue, anorexia, “flu-like” symptoms, dark urine, or jaundice. Periodic complete blood counts are recommended to monitor for potential hematological effects. Patients with glucose-6-phosphate dehydrogenase deficiency should be monitored for possible hemolytic anemia. Caution is advised when administering to patients with pre-existing hepatic conditions. Patients should avoid alcohol consumption during therapy due to potential additive hepatotoxicity.

Contraindications

Eulexin is contraindicated in patients with known hypersensitivity to flutamide or any component of the formulation. It should not be administered to patients with severe hepatic impairment (Child-Pugh Class C). The medication is contraindicated in women, particularly during pregnancy, due to potential teratogenic effects and lack of indication in female populations. It must not be used as monotherapy for prostate cancer treatment, as this may lead to disease flare from testosterone surge. Concomitant use with strong CYP1A2 inhibitors should be avoided unless benefits clearly outweigh risks.

Possible side effects

Common (≥10%): Hot flashes (50-60%), decreased libido (30-40%), impotence (30-40%), diarrhea (10-15%), nausea (10-12%), breast tenderness (10-15%)

Less common (1-10%): Vomiting, increased liver enzymes, insomnia, fatigue, dizziness, edema, hypertension, rash, pruritus

Rare (<1%): Hepatotoxicity (including hepatic necrosis and hepatic failure), hemolytic anemia, methemoglobinemia, photosensitivity reactions, lupus-like syndrome, interstitial lung disease

Laboratory abnormalities: Elevated transaminases, increased bilirubin, anemia, leukopenia, thrombocytopenia

Drug interactions

• Warfarin: Increased anticoagulant effect; monitor PT/INR closely and adjust warfarin dosage as needed
• CYP1A2 inhibitors (fluvoxamine, ciprofloxacin): May increase flutamide concentrations
• CYP1A2 inducers (smoking, omeprazole): May decrease flutamide efficacy
• Theophylline: Potential for increased theophylline levels
• Other hepatotoxic medications: Additive risk of liver damage; requires enhanced monitoring

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next scheduled dose. In that case, the missed dose should be skipped, and the regular dosing schedule resumed. Patients should not double the dose to make up for a missed administration. Consistent timing is important to maintain stable drug levels, but occasional missed doses are not typically critical given the medication’s mechanism of action. Patients should inform their healthcare provider if multiple doses are missed or if adherence becomes problematic.

Overdose

There is limited experience with flutamide overdose. Symptoms may include nausea, vomiting, dizziness, and potential hepatic toxicity. In case of suspected overdose, gastric lavage or activated charcoal administration may be considered if presentation is early. Supportive care should be initiated, including monitoring of vital signs and liver function. There is no specific antidote for flutamide overdose. Hemodialysis is unlikely to be effective due to high protein binding. Management should focus on symptomatic treatment and supportive measures, with particular attention to potential hepatic effects.

Storage

Store at controlled room temperature (20-25°C or 68-77°F) in the original container with the lid tightly closed. Protect from light and moisture. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Do not transfer tablets to other containers, as the original packaging provides necessary protection from environmental factors. Proper disposal of unused medication should follow local regulations for pharmaceutical waste.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Treatment decisions must be made by qualified healthcare professionals based on individual patient characteristics and current clinical guidelines. The prescribing physician should be consulted for specific dosage recommendations and management of adverse effects. Actual product characteristics and prescribing information may vary by region and should be verified with local regulatory authorities. Patients should not alter or discontinue medication without medical supervision.

Reviews

Clinical evidence: Multiple randomized controlled trials have demonstrated the efficacy of Eulexin in combination with LHRH agonists for metastatic prostate cancer. The combination shows statistically significant improvements in progression-free survival compared to monotherapy in appropriate patient populations.

Expert consensus: Urological and oncological guidelines consistently recommend combined androgen blockade with flutamide or alternative antiandrogens for metastatic disease, noting the established efficacy and manageable safety profile with appropriate monitoring.

Patient reported outcomes: Many patients report effective control of cancer-related symptoms, though quality of life impacts from side effects (particularly hot flashes and sexual dysfunction) require ongoing management and patient education.