Flutamide
Pronunciation: (FLOO-ta-mide).
- Generic name
- Flutamide
- Brand names
- Cytomid, Chironal, Flutafine, Euflex, Eulexin, Drogenil
- Drug class
- Nonsteroidal Antiandrogen (NSAA)
Availability and supply rules vary by country
Trade names by country: United States
Australia: · Full directory
What Flutamide is and how it works
Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.
Mechanism of action: how Flutamide works
Flutamide is a nonsteroidal antiandrogen that competitively inhibits the binding of androgens (such as testosterone and dihydrotestosterone) to androgen receptors in prostate tissue. This blockade prevents androgen-driven growth of prostate cancer cells, reducing tumor progression. (1) (2)
What Flutamide is used for
Prostate cancer
Used together with a luteinizing hormone-releasing hormone (LHRH) agonist to manage locally confined Stage B2-C and Stage D2 metastatic prostate cancer. This is the only FDA-approved use of flutamide. (2)
Before taking Flutamide
Do not take / not appropriate for
- severe hepatic impairment, known hypersensitivity to flutamide, and use in women who are or may become pregnant. (Contraindication) (2)
Tell your clinician about
(2)How to take Flutamide
- General Instructions: Take flutamide exactly as prescribed by your healthcare provider. It is usually taken three times a day, at evenly spaced intervals.. Adult Dosing: The typical adult dose for prostate cancer is 250 mg orally every 8 hours (three times daily).. Pediatric Dosing: Flutamide is not recommended for use in children.. Administration: Swallow the tablet whole with a glass of water. It can be taken with or without food, but taking it with food may help reduce stomach upset.. When To Stop: Do not stop taking flutamide without consulting your doctor, even if you feel well. Your doctor will advise when it is safe to discontinue.. Storage: Store at room temperature (20–25°C/68–77°F), away from moisture and heat. Keep out of reach of children.
- This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (2)
Missed dose
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 resume your regular schedule. Do not take an extra dose to catch up.
Overdose
In case of overdose, seek emergency medical attention or contact a poison control center immediately. Symptoms may include drowsiness, vomiting, tremor, or methemoglobinemia (bluish skin/lips). Supportive care is the mainstay of treatment. (2)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.
Hot flashes
Incidence: About 61% of patients when used with an LHRH agonist
Diarrhea
Incidence: About 12% of patients when used with an LHRH agonist
Nausea and vomiting
Incidence: About 11% of patients when used with an LHRH agonist
Liver toxicity
Incidence: Reported in the clinician-authored database; frequency not established (see boxed warning)
Gynecomastia
Incidence: Reported in the clinician-authored database; frequency not established
Decreased libido
Incidence: About 36% of patients when used with an LHRH agonist
Impotence
Incidence: About 33% of patients when used with an LHRH agonist
Breast tenderness
Incidence: Reported in the clinician-authored database; frequency not established
Serious warnings
BOXED WARNING — serious
Symptoms: BOXED WARNING: There have been postmarketing reports of hospitalization and, rarely, death due to liver failure in patients taking flutamide; about half of these cases occurred within the first 3 months of treatment. Liver function tests are required before starting therapy, monthly for the first 4 months, and periodically thereafter. Seek immediate medical attention if you notice signs of liver problems, such as yellowing of the skin or eyes, dark urine, unusual tiredness, or nausea — your clinician will evaluate your liver function and advise whether flutamide should be continued or stopped.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Serious liver toxicity can occur — serious
Symptoms: Serious liver toxicity can occur; regular liver function monitoring is required. Not for use in women, especially during pregnancy or breastfeeding. May cause gynecomastia (breast enlargement) and breast tenderness in men. Can interact with other medications, especially warfarin and hepatotoxic drugs. May cause hot flashes, gastrointestinal upset, and changes in urine color.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Contraindications recorded in the clinician database — serious
Symptoms: Contraindications recorded in the clinician database: Contraindications include severe hepatic impairment, known hypersensitivity to flutamide, and use in women who are or may become pregnant. Precautions include monitoring for hepatotoxicity, caution in patients with pre-existing liver disease, and careful use in those with cardiovascular risk factors.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Recorded interactions | Flutamide may interact with anticoagulants (such as warfarin), increasing the risk of bleeding. It can also interact with other medications that are metabolized by the liver, potentially increasing the risk of liver toxicity. Always inform your healthcare provider of all medications and supplements you are taking. | (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Flutamide is Pregnancy Category D and may cause fetal harm if used by a pregnant woman. Flutamide is approved for use in men only and is not used to treat women. (2)
Breastfeeding
Flutamide is not used in women, so breastfeeding guidance for this medicine is not applicable in typical clinical use. (2)
Children
Frequency: Not applicable.. Weight Based: Not recommended for pediatric use.. Max Daily Dose: Not applicable.. Max Single Dose: Not applicable.. Age Restrictions: Safety not established in children. (2)
Renal_impairment
Renal: the FDA label states no correlation was found between creatinine clearance and flutamide/active-metabolite exposure; in patients with creatinine clearance <29 mL/min the active metabolite's half-life was slightly prolonged, but dose adjustment in chronic renal insufficiency is not considered necessary (flutamide and its metabolite are not well dialyzed). Hepatic: flutamide carries an FDA boxed warning for serious/fatal hepatotoxicity and is contraindicated in severe hepatic impairment; the label states no pharmacokinetic data in hepatic impairment are available, and regular liver-function monitoring is required throughout treatment. (2)
Hepatic_impairment
Renal: the FDA label states no correlation was found between creatinine clearance and flutamide/active-metabolite exposure; in patients with creatinine clearance <29 mL/min the active metabolite's half-life was slightly prolonged, but dose adjustment in chronic renal insufficiency is not considered necessary (flutamide and its metabolite are not well dialyzed). Hepatic: flutamide carries an FDA boxed warning for serious/fatal hepatotoxicity and is contraindicated in severe hepatic impairment; the label states no pharmacokinetic data in hepatic impairment are available, and regular liver-function monitoring is required throughout treatment. (2)
Monitoring
(2)Storage
Store at room temperature, 20-25°C (68-77°F), in a tightly closed, light-resistant container with a child-resistant closure. Keep out of reach of children.
Professional information
Clinician-facing context only. This section does not replace current product labeling.
General
Indication: Prostate cancer (with an LHRH agonist)
Dose summary: Flutamide 250 mg orally three times daily, used together with an LHRH agonist.
Renal context: The FDA label found no correlation between creatinine clearance and flutamide exposure; in patients with CrCl <29 mL/min the active metabolite's half-life was slightly prolonged, but dose adjustment in chronic renal insufficiency is not considered necessary. Flutamide and its active metabolite are not well removed by dialysis. (1) (2)
Hepatic guidance
Flutamide carries an FDA BOXED WARNING for serious, sometimes fatal, hepatotoxicity, and is contraindicated in patients with severe hepatic impairment. The label states no pharmacokinetic data in hepatic impairment are available; baseline and regular liver-function monitoring is required throughout treatment, and patients should be told to watch for signs of liver injury (e.g. jaundice, dark urine, right-upper-quadrant pain).
Frequently asked questions
What is flutamide used for?
Flutamide is primarily used to treat advanced prostate cancer in men. It is often combined with other hormone therapies to slow the growth of cancer cells.
How does flutamide work?
Flutamide blocks the action of male hormones (androgens) like testosterone, which can stimulate the growth of prostate cancer cells.
What are the most common side effects?
The most common side effects are diarrhea, nausea, vomiting, tiredness, and mild breast tenderness or enlargement.
Can women take flutamide?
Flutamide is not recommended for use in women, especially those who are pregnant or breastfeeding, due to potential harm to the fetus or infant.
What should I do if I miss a dose?
Take the missed dose as soon as you remember, unless it is almost time for your next dose. Do not take an extra dose to make up for it.
How is liver function monitored during flutamide therapy?
Your doctor will order regular blood tests to check your liver enzymes and function while you are taking flutamide.
Is flutamide a cure for prostate cancer?
No, flutamide is not a cure. It helps manage symptoms and slow the progression of prostate cancer.
What happens if I take too much Flutamide?
Taking too much Flutamide can lead to an exacerbation of side effects, including nausea, vomiting, and liver dysfunction. In severe cases, overdose may manifest as methemoglobinemia. If an overdose is suspected, it is crucial to seek immediate emergency medical attention. Do not attempt to induce vomiting or self-treat.
Can I drink alcohol while taking Flutamide?
It is generally advisable to limit or avoid alcohol consumption while taking Flutamide. Both Flutamide and alcohol are metabolized by the liver, and their concurrent use can increase the risk of liver damage and exacerbate potential hepatotoxicity associated with the drug. Consult your healthcare provider for personalized advice regarding alcohol intake.
Is Flutamide safe during pregnancy?
Flutamide is Pregnancy Category D and may cause fetal harm. It is approved for use in men only and is not used to treat women, so it should never be taken by someone who is or may become pregnant.
What is the mechanism of action of Flutamide?
Flutamide is a nonsteroidal antiandrogen that competitively inhibits the binding of androgens (such as testosterone and dihydrotestosterone) to androgen receptors in prostate tissue. This blockade prevents androgen-driven growth of prostate cancer cells, reducing tumor progression. (1) (2)
What is the generic name of Flutamide?
The generic name is Flutamide. It is sold under brand names including Cytomid, Chironal, Flutafine, Euflex, Eulexin, Drogenil.
What class of drug is Flutamide?
Flutamide is classed as: Nonsteroidal Antiandrogen (NSAA).
References
- Flutamide - MedGuideGlobal Clinician-Authored Medicine RecordMedGuideGlobal Internal Clinician Record · Global (Internal) · accessed 2026-08-06 · source 1
- EULEXIN (flutamide) capsule - FDA prescribing informationU.S. National Library of Medicine, DailyMed (FDA-approved label) · United States · accessed 2026-08-06 · source 2
- EULEXIN (FLUTAMIDE) CAPSULE [WAYLIS THERAPEUTICS LLC] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
- Flutamide — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 4
- Eulexin — FDA approval record (Drugs@FDA ANDA075298)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
- Flutamide — RxNorm normalized drug concept (RXCUI 4508)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6
Brand names by country
Single-ingredient Flutamide names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Eulexin125 mg · waylis therapeutics llc