Mycobutin Side Effects

Generic name: rifabutin

Medically reviewed by Drugs.com. Last updated on Mar 21, 2025.

Note: This document provides detailed information about Mycobutin Side Effects associated with rifabutin. Some dosage forms listed on this page may not apply specifically to the brand name Mycobutin.

Applies to rifabutin: oral capsule.

Serious side effects of Mycobutin

Along with its needed effects, rifabutin (the active ingredient contained in Mycobutin) 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 rifabutin:

Less common side effects

• black, tarry stools
• chest pain
• chills
• cough
• diarrhea
• fever
• heartburn
• indigestion
• itching or skin rash
• loss of appetite
• loss of strength or energy
• muscle pain
• painful or difficult urination
• sore throat
• ulcers, sores, or white spots in the mouth
• unusual bleeding or bruising
• unusual tiredness or weakness

Rare side effects

• bruising or purple spots on the skin
• change in taste
• eye pain
• joint pain
• loss of vision
• lower back or side pain
• muscle swelling or pain
• pale skin
• yellow skin

Incidence not known

• burning, dry, or itching eyes
• discharge, excessive tearing
• hoarseness
• redness, pain, swelling of the eye, eyelid, or inner lining of the eyelid
• stomach cramps, pain, or tenderness
• watery and severe diarrhea, which may also be bloody

Other side effects of Mycobutin

Some side effects of rifabutin 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:

Less common side effects

• bad, unusual, or unpleasant (after) taste in the mouth
• belching
• bloated or full feeling
• discoloration of the urine
• excess air or gas in the stomach or intestines
• headache
• nausea
• passing gas
• trouble sleeping

For healthcare professionals

Applies to rifabutin: oral capsule.

Cardiovascular adverse events

• Frequency not reported: Nonspecific T wave changes on ECG

Dermatologic

• Very common (10% or more): Rash (up to 11%)
• Uncommon (0.1% to 1%): Skin discoloration
• Frequency not reported: Severe cutaneous adverse reactions
• Postmarketing reports: Rash, skin discoloration, drug reaction with eosinophilia and systemic symptoms [DRESS], severe cutaneous adverse reactions

There have been reports of DRESS and other severe cutaneous adverse reactions (e.g., Stevens-Johnson syndrome, toxic epidermal necrolysis, acute generalized exanthematous pustulosis) associated with this drug.

Gastrointestinal

• Common (1% to 10%): Nausea, gastrointestinal intolerance/symptoms, abdominal pain, diarrhea, dyspepsia, eructation, flatulence, nausea and vomiting, vomiting
• Postmarketing reports: Clostridioides difficile associated diarrhea, C difficile colitis

Rifamycin Class Antibiotics:

• Frequency not reported: C difficile colitis

Genitourinary

• Very common (10% or more): Discolored urine (up to 30%)

Hematologic

• Very common (10% or more): Neutropenia (up to 25%), leukopenia (up to 17%)
• Common (1% to 10%): Anemia, eosinophilia, thrombocytopenia
• Uncommon (0.1% to 1%): Pancytopenia, agranulocytosis, lymphopenia, granulocytopenia, decreased WBC count, decreased neutrophil count, decreased platelet count
• Rare (0.01% to 0.1%): Hemolysis
• Frequency not reported: Thrombotic thrombocytopenic purpura, blood/lymphatic system disorders
• Postmarketing reports: WBC disorders, decreased platelet count, eosinophilia

Neutropenia (absolute neutrophil count less than 750/mm3), leukopenia (WBC values less than 1500/mm3), anemia (hemoglobin values less than 8 g/dL), and thrombocytopenia (platelet count values less than 50,000/mm3) have been reported in 25%, 17%, 6%, and 5% of patients, respectively.

WBC disorders included agranulocytosis, leukopenia, lymphopenia, granulocytopenia, neutropenia, decreased WBC count, and decreased neutrophil count.

Hepatic

• Very common (10% or more): Jaundice (up to 12%)
• Common (1% to 10%): Increased AST, increased ALT
• Uncommon (0.1% to 1%): Increased hepatic enzymes
• Rare (0.01% to 0.1%): Hepatitis
• Frequency not reported: Abnormal liver function tests

Increased AST (greater than 150 units/L) and ALT (greater than 150 units/L) have been reported in 9% and 7% of patients, respectively.

Hypersensitivity

• Uncommon (0.1% to 1%): Hypersensitivity
• Postmarketing reports: Hypersensitivity

Rifamycin Class Antibiotics:

• Frequency not reported: Anaphylactic shock
• Postmarketing reports: Hypersensitivity

Hypersensitivity to rifamycins have been reported, including influenza-like symptoms, bronchospasm, hypotension, urticaria, angioedema, conjunctivitis, thrombocytopenia, or neutropenia.

Metabolic

• Common (1% to 10%): Anorexia

Musculoskeletal

• Common (1% to 10%): Myalgia
• Uncommon (0.1% to 1%): Arthralgia
• Frequency not reported: Myositis, generalized arthralgia

Nervous system

• Common (1% to 10%): Headache, taste perversion
• Frequency not reported: Seizure, paresthesia, aphasia

Ocular

• Uncommon (0.1% to 1%): Uveitis, corneal deposits

Other

• Common (1% to 10%): Pyrexia, asthenia, chest pain, fever, pain
• Frequency not reported: Influenza-like syndrome, chest pressure/pain, increased alkaline phosphatase

Chest pressure or pain with dyspnea has been reported.

Increased alkaline phosphatase (greater than 450 units/L) has been reported in less than 1% of patients.

Psychiatric

• Common (1% to 10%): Insomnia
• Frequency not reported: Confusion

Respiratory

• Uncommon (0.1% to 1%): Bronchospasm
• Frequency not reported: Dyspnea
• Postmarketing reports: Bronchospasm

Further information

Mycobutin 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.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer