Flutamide

Commonly reported side effects of flutamide include: diarrhea. See below for a comprehensive list of adverse effects.

Applies to flutamide: oral capsule

Along with its needed effects, flutamide may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking flutamide:

More common

• Black, tarry stools
• bloody or cloudy urine
• continuing diarrhea
• continuing stomach pain
• difficult, burning, or painful urination
• frequent urge to urinate
• pale skin
• troubled breathing with exertion
• unusual bleeding or bruising
• unusual tiredness or weakness

Less common

• Blurred vision
• chest pain
• chills
• cough
• difficulty with breathing
• dizziness
• drowsiness
• fever
• headache
• nervousness
• pounding in the ears
• shortness of breath
• slow or fast heartbeat
• sore throat
• sores, ulcers, or white spots on the lips or in the mouth
• swelling
• swollen glands

Rare

• Abdominal or stomach pain
• clay-colored stools
• dark urine
• general tiredness and weakness
• itching
• light-colored stools
• loss of appetite
• nausea and vomiting
• rash
• tumor
• unpleasant breath odor
• upper right abdominal pain
• vomiting of blood
• yellow eyes and skin

Incidence not known

• Back, leg, or stomach pains
• bleeding gums
• blistering, peeling, or loosening of the skin
• bluish-colored lips, fingernails, or palms
• discoloration of the urine
• dizziness or lightheadedness
• flushing or redness of the skin
• general body swelling
• headache
• itching
• joint or muscle pain
• nosebleeds
• rapid heart rate
• red irritated eyes
• red skin lesions, often with a purple center
• unusually warm skin

Get emergency help immediately if any of the following symptoms of overdose occur while taking flutamide:

Symptoms of overdose

• Goosebumps
• shakiness and unsteady walk
• tearing of the eyes
• unsteadiness, trembling, or other problems with muscle control or coordination
• weight loss

Some side effects of flutamide may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Decreased interest in sexual intercourse
• diarrhea
• feeling of warmth
• inability to have or keep an erection
• indigestion
• loss in sexual ability, desire, drive, or performance
• passing of gas
• redness of the face, neck, arms and occasionally, upper chest
• stomach pain, fullness, or discomfort
• sudden sweating
• swelling of the breasts or breast soreness in both females and males

Less common

• Depression
• drowsiness
• fear or nervousness
• mood or mental changes

Applies to flutamide: oral capsule

Rare (0.01% to 0.1%): Abnormal liver function tests, hepatic dysfunction, jaundice

Very rare (less than 0.01%): Cholestatic jaundice, hepatic encephalopathy, liver cell necrosis, fatal hepatotoxicity

Rare (0.01% to 0.1%): Anemia, leucopenia, thrombocytopenia

Very rare (less than 0.01%): Hemolytic anemia, megalocytic anemia, methemoglobinemia, sulfhemoglobinemia, macrocytic anemia

Rare (less than 0.1%): Dizziness, headache, numbness, drowsiness

Frequency not reported: Tiredness, malaise

Very common (10% or more): Hot flushes

Rare (less than 0.1%): Cardiovascular disorders, hypertension, lymphoedema

Frequency not reported: QT prolongation, thromboembolism

Rare (0.01% to 0.1%): Urticaria, pruritus, ecchymosis, alteration of the hair growth pattern and loss of hair (head), rash

Very rare (less than 0.01%): Photosensitivity reactions, erythema, ulcers, bullous eruptions, epidermal necrosis

Very common (10% or more): Gynecomastia (19%)

Common (1% to 10%): Breast tenderness (7%)

Very common (10% or more): Nausea, vomiting, diarrhea

Rare (less than 0.1%): Constipation, ulcer-like pain, dyspepsia, colitis, upset stomach, heartburn, abdominal pain

Rare (0.01% to 0.1%): Muscle cramps, neuromuscular symptoms, reduced bone mineral density, osteoporotic disorders, arthralgia, myalgia

Rare (0.01% to 0.1%): Anxiety, depression, confusion, nervousness

Frequency not reported: Loss of libido

Rare (0.01% to 0.1%): Interstitial pneumonitis, dyspnea

Very rare (less than 0.01%): Cough, interstitial lung disease

Rare (0.01% to 0.1%): Lupus-like syndrome

Very rare (less than 0.01%): Herpes zoster

Rare (less than 0.1%): Blurred vision

Common (1% to 10%): Increased appetite

Rare (less than 0.1%): Anorexia

Very rare (less than 0.01%): Neoplasm of the male breast