Flutamide
/api/v1/drug/flutamideBoxed warning
Hepatic Injury There have been postmarketing reports of hospitalization and rarely death due to liver failure in patients taking Eulexin ® . Evidence of hepatic injury included elevated serum transaminase levels, jaundice, hepatic encephalopathy and death related to acute hepatic failure. The hepatic injury was reversible after discontinuation of therapy in some patients. Approximately half of the reported cases occurred within the initial 3 months of treatment with Eulexin ® . Serum transaminase levels should be measured prior to starting treatment with Eulexin ® . Eulexin ® is not recommended in patients whose ALT values exceed twice the upper limit of normal. Serum transaminase levels should then be measured monthly for the first 4 months of therapy, and periodically thereafter. Liver function tests also should be obtained at the first signs and symptoms suggestive of liver dysfunction, e.g., nausea, vomiting, abdominal pain, fatigue, anorexia, "flu-like" symptoms, hyperbilirubinuria, jaundice or right upper quadrant tenderness. If at any time, a patient has jaundice, or their ALT rises above 2 times the upper limit of normal, Eulexin ® should be immediately discontinued with close follow-up of liver function tests until resolution.
Mechanism of action
Sourced from openFDAMechanism-of-action class: Androgen Receptor Antagonists.
Indications
Sourced from openFDA- Eulexin ® capsules are indicated for use in combination with LHRH-agonists for the management of locally confined Stage B 2 -C and Stage D 2 metastatic carcinoma of the prostate. Stage B 2 -C Prostatic Carcinoma Treatment with Eulexin ® capsules and the goserelin acetate implant should start eight weeks prior to initiating radiation therapy and continue during radiation therapy.
Contraindications
Sourced from openFDA- Eulexin ® capsules are contraindicated in patients who are hypersensitive to Eulexin ® or any component of this preparation. Eulexin ® capsules are contraindicated in patients with severe hepatic impairment (baseline hepatic enzymes should be evaluated prior to treatment).contraindicated
Dosage & administration
Sourced from openFDAThe recommended dosage is 2 capsules 3 times a day at 8 hour intervals for a total daily dose of 750 mg.
Warnings & precautions
Sourced from openFDAHepatic Injury SEE BOXED WARNINGS Use in Women Eulexin ® capsules are for use only in men. This product has no indication for women and should not be used in this population, particularly for nonserious or nonlife-threatening conditions. Fetal toxicity Eulexin ® may cause fetal harm when administered to a pregnant woman (see Pregnancy ). Aniline toxicity One metabolite of Eulexin ® is 4-nitro-3-fluoro-methylaniline. Several toxicities consistent with aniline exposure, including methemoglobinemia, hemolytic anemia and cholestatic jaundice have been observed in both animals and humans after Eulexin ® administration. In patients susceptible to aniline toxicity (e.g. persons with glucose-6-phosphate dehydrogenase deficiency, hemoglobin M disease and smokers), monitoring of methemoglobin levels should be considered.
Adverse reactions
Sourced from openFDAStage B 2 -C Prostatic Carcinoma Treatment with Eulexin ® capsules and the goserelin acetate implant did not add substantially to the toxicity of radiation treatment alone. The following adverse experiences were reported during a multicenter clinical trial comparing Eulexin ® + goserelin acetate implant + radiation versus radiation alone. The most frequently reported (greater than 5%) adverse experiences are listed below: Adverse Events During Acute Radiation Therapy (within first 90 days of radiation therapy) (n=231) Goserelin Acetate Implant + Eulexin ® + Radiation (n=235) Radiation Only % All % All Rectum/Large Bowel 80 76 Bladder 58 60 Skin 37 37 Adverse Events During Late Radiation Phase (after 90 days of radiation therapy) (n=231) Goserelin Acetate Implant + Eulexin ® + Radiation (n=235) Radiation Only % All % All Diarrhea 36 40 Cystitis 16 16 Rectal Bleeding 14 20 Proctitis 8 8 Hematuria 7 12 Additional adverse event data were collected for the combination therapy with radiation group over both the hormonal treatment and hormonal treatment plus radiation phases of the study. Adverse experiences occurring in more than 5% of patients in this group, over both parts of the study, were hot flashes (46%), diarrhea (40%), nausea (9%), and skin rash (8%). Stage D 2 Metastatic Carcinoma The following adverse experiences were reported during a multicenter clinical trial comparing Eulexin ® + LHRH agonist versus placebo + LHRH agonist.
Use in specific populations
Sourced from openFDAPregnancy Pregnancy Category D There was decreased 24 hour survival in the offspring of pregnant rats treated with Eulexin ® at doses of 30, 100 or 200 mg/kg/day (approximately 3, 9 and 19 times the human dose). A slight increase in minor variations in the development of the sternebrae and vertebrae was seen in fetuses of rats treated with two higher doses. Feminization of the male rats also occurred at the two higher dose levels. There was a decreased survival rate in the offspring of rabbits receiving the highest dose (15 mg/kg/day, equal to 1.4 times the human dose).
Pharmacokinetics
Sourced from openFDA- Metabolism
- Absorption Analysis of plasma, urine, and feces following a single oral 200 mg dose of tritium-labeled Eulexin ® to human volunteers showed that the drug is rapidly and completely absorbed. Following a single 250 mg oral dose to normal adult volunteers, the biologically active alpha-hydroxylated metabolite reaches maximum plasma concentrations in about 2 hours, indicating that it is rapidly formed from flutamide.
Overdosage
Sourced from openFDAIn animal studies with Eulexin ® alone, signs of overdose included hypoactivity, piloerection, slow respiration, ataxia, and/or lacrimation, anorexia, tranquilization, emesis, and methemoglobinemia. Clinical trials have been conducted with Eulexin ® in doses up to 1500 mg per day for periods up to 36 weeks with no serious adverse effects reported. Those adverse reactions reported included gynecomastia, breast tenderness, and some increases in SGOT. The single dose of Eulexin ® ordinarily associated with symptoms of overdose or considered to be life-threatening has not been established. Eulexin ® is highly protein bound, and is not cleared by hemodialysis. As in the management of overdosage with any drug, it should be borne in mind that multiple agents may have been taken. If vomiting does not occur spontaneously, it should be induced if the patient is alert. General supportive care, including frequent monitoring of the vital signs and close observation of the patient, is indicated.
Approval history
Sourced from openFDA- Sep 18, 2001ANDAANDA075298Waylis Therap
FAERS reports
- 1Prostate Cancer707.1%
- 2Anaemia656.6%
- 3Fatigue636.4%
- 4Prostatic Specific Antigen Increased606.1%
- 5Asthenia464.7%
- 6Death454.6%
- 7Diarrhoea414.2%
- 8Nausea373.8%
- 9Metastases To Bone363.7%
- 10Pain353.6%
- 11Malaise333.4%
- 12Malignant Neoplasm Progression333.4%
- 13Back Pain323.3%
- 14Drug Ineffective323.3%
- 15Rash313.2%
Literature
Recent PubMed references pinned to Flutamide as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.
- Gut microbial metabolism of Flutamide attenuates its therapeutic efficacy against prostate cancer.Gut microbes · 2026 · Li S, Ding H, Wang J, et al.PMID 42252578DOI 10.1080/19490976.2026.2682803
- Late gestational exposure to flutamide alters stromal composition and immune landscape in the rat mammary gland during pre-puberty, peri-puberty, and adulthood.Toxicological sciences : an official journal of the Society of Toxicology · 2026 · Tovar Parra D, McDermott A, Cardot J, et al.PMID 42155037DOI 10.1093/toxsci/kfag053
- Maternal flutamide exposure induces spermatogenic dysfunction in male offspring: The mechanistic role of RARα-Mediated NLRP3 inflammasome activation.Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association · 2026 · Long C, Wang S, Hong Y, et al.PMID 42067019DOI 10.1016/j.fct.2026.116107
- Flutamide exacerbates hepatic insulin resistance in type 2 diabetic mice through overproduction of ROS and activation of NLRP3 signaling.International immunopharmacology · 2026 · Zhang Y, Zhang Y, Xiang Q, et al.PMID 42034939DOI 10.1016/j.intimp.2026.116683
- Innovative Se-Flutamide Derivatives: Enhanced Activity Toward Androgen Receptor (AR)-Dependent and -Independent Prostate Cancer Cells.Archiv der Pharmazie · 2025 · Morán-Serradilla C, Sanmartín C, Raza A, et al.PMID 41103090DOI 10.1002/ardp.70119
- Androgen receptor antagonist flutamide modulates estrogen receptor alpha expression in distinct regions of the hypospadiac rat penis.Frontiers in endocrinology · 2025 · Elmelund E, Draskau MK, Berg M, et al.PMID 41019341DOI 10.3389/fendo.2025.1654965
- Analysis of miRNA expression profiles during spermatogenesis of plateau zokor (Eospalax baileyi) under androgen antagonism treatment.Comparative biochemistry and physiology. Part D, Genomics & proteomics · 2025 · Ou K, An K, Hao B, et al.PMID 40961732DOI 10.1016/j.cbd.2025.101636
- Short-term Androgen Deprivation Therapy and High-dose Radiotherapy in Intermediate- and High-risk Localized Prostate Cancer: Results from the GETUG 14 Randomized Phase 3 Trial.European urology · 2025 · Demogeot N, Sargos P, Salleron J, et al.PMID 40816927DOI 10.1016/j.eururo.2025.07.019
Clinical trials
The 10 most recently updated of 78 ClinicalTrials.gov registrations naming Flutamide as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.
- Trial Comparing Irradiation Plus Long Term Adjuvant Androgen Deprivation With GnRH Antagonist Versus GnRH Agonist Plus Flare Protection in Patients With Very High Risk Localized or Locally Advanced Prostate CancerActive not recruiting · Phase 3 · Interventional · 885 enrolled · European Organisation for Research and Treatment of Cancer - EORTCNCT02799706updated 2026-05-22
- Antiandrogen Therapy and Radiation Therapy With or Without Docetaxel in Treating Patients With Prostate Cancer That Has Been Removed by SurgeryCompleted · Phase 2 · Phase 3 · Interventional · 612 enrolled · NRG OncologyNCT03070886updated 2026-05-07
- Two Studies for Patients With Unfavorable Intermediate Risk Prostate Cancer Testing Less Intense Treatment for Patients With a Low Gene Risk Score and Testing a More Intense Treatment for Patients With a Higher Gene Risk Score, The Guidance TrialActive not recruiting · Phase 3 · Interventional · 2,050 enrolled · NRG OncologyNCT05050084updated 2026-05-04
- Two Studies for Patients With High Risk Prostate Cancer Testing Less Intense Treatment for Patients With a Low Gene Risk Score and Testing a More Intense Treatment for Patients With a High Gene Risk Score, The PREDICT-RT TrialActive not recruiting · Phase 3 · Interventional · 2,753 enrolled · NRG OncologyNCT04513717updated 2026-05-04
- Phase I/II Study of [225Ac]Ac-PSMA-R2 in PSMA-positive Prostate Cancer, With/Without Prior 177Lu-PSMA RLTActive not recruiting · Phase 1 · Phase 2 · Interventional · 33 enrolled · Novartis PharmaceuticalsNCT05983198updated 2026-04-29
- Adaptive Stereotactic Body Radiation Therapy to the Prostate and Pelvic Nodes With Simultaneous Integrated Boost to the MR-detected Nodule for Patients With High-risk and Unfavorable Intermediate-risk Prostate CancerActive not recruiting · Interventional · 28 enrolled · Washington University School of MedicineNCT05628363updated 2026-04-29
- Veterans Affairs Seamless Phase II/III Randomized Trial of STAndard Systemic theRapy With or Without PET-directed Local Therapy for Oligometastatic pRosTate CancerRecruiting · Phase 2 · Phase 3 · Interventional · 464 enrolled · VA Office of Research and DevelopmentNCT04787744updated 2026-04-08
- Radiation Therapy With or Without Androgen-Deprivation Therapy in Treating Patients With Prostate CancerCompleted · Phase 3 · Interventional · 1,538 enrolled · Radiation Therapy Oncology GroupNCT00936390updated 2026-03-06
- Hormone Therapy, Radiation Therapy, and Steroid 17alpha-monooxygenase TAK-700 in Treating Patients With High-Risk Prostate CancerCompleted · Phase 3 · Interventional · 239 enrolled · Radiation Therapy Oncology GroupNCT01546987updated 2026-03-06
- Contributions to Hypertension With Androgen Deprivation TherapyCompleted · Phase 4 · Interventional · 10 enrolled · University of Colorado, DenverNCT05700903updated 2026-03-02
Frequently asked questions
- How does Flutamide work?
- Mechanism-of-action class: Androgen Receptor Antagonists.
- What is Flutamide used for?
- According to FDA labeling, Flutamide carries indications including: Eulexin ® capsules are indicated for use in combination with LHRH-agonists for the management of locally confined Stage B 2 -C and Stage D 2 metastatic carcinoma of the prostate. Stage B 2 -C Prostatic Carcinoma Treatment with Eulexin ® capsules and the goserelin acetate implant should start eight weeks prior to initiating radiation therapy and continue during radiation therapy.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.
- What class of drug is Flutamide?
- Flutamide is classified as Anti-androgens, Androgen Receptor Inhibitor, Androgen Receptor Antagonists, Testicular Endocrine Activity Alteration.
- What are the brand names for Flutamide?
- Flutamide is marketed under brand names including Eulexin.
- What are the contraindications for Flutamide?
- Flutamide labeling lists contraindications including: Eulexin ® capsules are contraindicated in patients who are hypersensitive to Eulexin ® or any component of this preparation. Eulexin ® capsules are contraindicated in patients with severe hepatic impairment (baseline hepatic enzymes should be evaluated prior to treatment).. Always consult the full prescribing information and a clinician.
flutamide is illustrative MVP content compiled from public sources. pharmacopeia is for educational and informational use only and is not a substitute for professional medical advice.