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Flutamide Side Effects

The most commonly reported side effects of flutamide include anaemia, fatigue, and prostate cancer, based on 1,019 FDA adverse event reports from 2004 to 2025. 2.9% of reports found the drug to be ineffective.

Flutamide side effects

Percentages show how often each reaction appears relative to total reports for flutamide.

1
Anaemia4.9%50
2
Fatigue4.7%48
3
Prostate Cancer4.4%45
4
Prostatic Specific Antigen Increased4.2%43
5
Prostate Cancer2.9%30
6
Drug Ineffective2.9%30
7
Off Label Use2.8%29
8
Rash2.7%28
9
Pain2.6%26
10
Death2.6%26
11
Malaise2.5%25
12
Asthenia2.3%23
13
Diarrhoea2.3%23
14
Malignant Neoplasm Progression2.3%23
15
Decreased Appetite2.3%23

These are voluntary reports and do not establish that flutamide caused these reactions.

Report severity

89.9%Serious916 reports
36.1%Hospitalizations368 reports
25.0%Fatal255 reports

Seriousness is determined by the reporter, not by OpenClaim.

Flutamide drug interactions

Other drugs that appear in adverse event reports alongside flutamide. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Leuprolide18.4%187
2
Enzalutamide11.8%120
3
Bicalutamide6.7%68
4
Docetaxel4.9%50
5
Goserelin4.7%48
6
Zoledronic-acid4.3%44
7
Finasteride3.9%40
8
Abiraterone-acetate3.8%39
9
Metformin3.1%32
10
Denosumab2.5%25
11
Estramustine-phosphate-sodium1.8%18
12
Dexamethasone1.8%18
13
Adalimumab1.8%18
14
Prednisone1.8%18
15
Spironolactone1.7%17

Taken alongside

1
Bicalutamide16.5%168
2
Aspirin8.5%87
3
Prednisone7.5%76
4
Acetaminophen6.5%66
5
Leuprolide6.2%63
6
Dexamethasone6.1%62
7
Amlodipine5.5%56
8
Furosemide5.5%56
9
Estramustine-phosphate-sodium5.4%55
10
Goserelin5.0%51
11
Tamsulosin-hydrochloride4.9%50
12
Metoprolol4.5%46
13
Oxycodone4.4%45
14
Metformin4.3%44
15
Calcium4.3%44

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports flutamide side effects

13.8% of flutamide adverse event reports involve female patients and 77.4% involve male patients. The largest age group is elderly at 78%. These figures reflect who reports side effects, not underlying risk.

Sex

Female13.8%
Male77.4%
Unknown8.7%

Age group

< 20.0%
2–110.4%
12–170.4%
18–6420.8%
65+78.4%

What is flutamide used for

Conditions and purposes for which patients were taking flutamide when the adverse event was reported.

AcneAdenocarcinomaAlopeciaAndrogen TherapyAndrogenetic AlopeciaAndrogens IncreasedAntiandrogen TherapyArrhythmiaArthritisAdenocarcinomaAlopeciaAntiandrogen TherapyArthritisBenign Prostatic HyperplasiaBlood Testosterone Abnormal

Showing 15 of 68 indications

Flutamide brand names and reporting trend

Flutamide is sold under the brand name Eulexin.

Brand names

Eulexin999

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking flutamide with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.