Flucytosine Side Effects

Medically reviewed by Drugs.com. Last updated on Jul 16, 2024.

Applies to flucytosine: oral capsule.

Important warnings This medicine can cause some serious health issues

Oral route (capsule)

Use with extreme caution in patients with impaired renal function.

Close monitoring of hematologic, renal, and hepatic status of all patients is essential.

Serious side effects of flucytosine

Along with its needed effects, flucytosine 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 flucytosine:

Incidence not known

• agitation
• black, bloody, tarry stools
• blistering, peeling, or loosening of the skin
• bloody or cloudy urine
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• burning upper abdominal or stomach pain
• change in consciousness
• chest pain or tightness
• chills
• confusion
• cough or hoarseness
• dark urine
• decreased urine output
• depression
• diarrhea
• dizziness
• dry mouth
• feeling of constant movement of self or surroundings
• fever
• headache
• hearing loss
• hives, itching, skin rash
• increased sensitivity of the skin to sunlight
• irregular heartbeat
• irritability
• joint or muscle pain
• light-colored stools
• loss of appetite
• loss of consciousness
• lower back or side pain
• mood changes
• muscle cramps or twitching
• nausea
• no blood pressure or pulse
• no breathing
• numbness or tingling in the hands, feet, or lips
• painful or difficult urination
• pain in the lower back or side
• pale skin
• rapid weight gain
• rectal bleeding
• red irritated eyes
• red skin lesions, often with a purple center
• redness of the skin
• seeing, hearing, or feeling things that are not there
• seizures
• sensation of spinning
• severe sunburn
• shakiness and unsteady walk
• sore throat
• sores, ulcers, or white spots on the lips or in the mouth
• stopping of the heart
• swelling of the face, ankles, or hands
• swollen glands
• thirst
• trouble breathing
• unpleasant breath odor
• unsteadiness, trembling, or other problems with muscle control or coordination
• unusual bleeding or bruising
• unusual drowsiness, dullness, tiredness, weakness or feeling of sluggishness
• vomiting
• vomiting of blood or material that looks like coffee grounds
• weakness in the arms, hands, legs, or feet
• weight loss
• yellow eyes or skin

For healthcare professionals

Applies to flucytosine: oral capsule.

Cardiovascular

• Frequency not reported: Cardiac arrest, myocardial toxicity, ventricular dysfunction, cardiac toxicity with ST elevation^[Ref]

Dermatologic

• Frequency not reported: Rash, pruritus, urticaria, photosensitivity, Lyell's syndrome^[Ref]

Gastrointestinal

• Frequency not reported: Nausea, vomiting/emesis, abdominal pain, diarrhea, dry mouth, duodenal ulcer, gastrointestinal hemorrhage/bleeding, enterocolitis, ulcerative colitis^[Ref]

Genitourinary

• Frequency not reported: Crystalluria^[Ref]

Hematologic

• Frequency not reported: Anemia, agranulocytosis, aplastic anemia, eosinophilia, leukopenia, pancytopenia, thrombocytopenia, bone marrow aplasia (fatal cases), bone marrow toxicity^[Ref]

Hepatic

• Frequency not reported: Jaundice, hepatic dysfunction, elevated bilirubin, increased hepatic enzymes, acute hepatic injury, hepatic necrosis, hepatitis, alterations in liver function tests^[Ref]

Acute hepatic injury including hepatic necrosis with possible fatal outcome in debilitated patients has been reported.

Alterations in liver function tests were generally dose related and reversible.^[Ref]

Hypersensitivity

• Frequency not reported: Allergic reactions, anaphylaxis^[Ref]

Metabolic

• Frequency not reported: Anorexia, hypoglycemia, hypokalemia

Nervous system

• Frequency not reported: Ataxia, hearing loss, headache, paresthesia, parkinsonism, peripheral neuropathy, vertigo, sedation, convulsions^[Ref]

Other

• Frequency not reported: Pyrexia, fatigue, weakness^[Ref]

Psychiatric

• Frequency not reported: Confusion, hallucinations, psychosis^[Ref]

Renal

• Frequency not reported: Azotemia, elevated creatinine, elevated BUN, renal failure^[Ref]

Respiratory

• Frequency not reported: Dyspnea, chest pain, respiratory arrest^[Ref]

Further information

Flucytosine side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer