Rifamate Side Effects

Generic name: isoniazid / rifampin

Medically reviewed by Drugs.com. Last updated on Oct 23, 2024.

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

Applies to isoniazid / rifampin: oral capsule.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• nausea, upper stomach pain, feeling weak or tired, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

• vision changes, confusion, hallucinations, unusual thoughts or behavior;

• fever, unusual weakness, pale skin; or

• easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin.

Common side effects may include:

• red-orange coloration of tears, sweat, saliva, urine, or stools;

• numbness, tingling, itching, mild rash;

• drowsiness, dizziness, headache;

• muscle pain or weakness;

• heartburn, gas, diarrhea; or

• mouth pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

See also:

For healthcare professionals

Applies to isoniazid / rifampin: oral capsule.

General adverse events

Doses greater than 600 mg of rifampin given once or twice weekly have resulted in a higher incidence of adverse reactions, including the "flu syndrome" (fever, chills, malaise); hematopoietic reactions (leukopenia, thrombocytopenia, acute hemolytic anemia); shortness of breath; shock; anaphylaxis; renal failure; and cutaneous, gastrointestinal, and hepatic reactions.^[Ref]

Cardiovascular

• Frequency not reported: Vasculitis

Rifampin:

• Frequency not reported: Flushing, decreased blood pressure^[Ref]

Dermatologic

• Frequency not reported: Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome, Stevens-Johnson syndrome, Toxic Epidermal Necrolysis (TEN), rash

Isoniazid:

• Frequency not reported: Acne, exfoliative dermatitis, pemphigus

Rifampin:

• Frequency not reported: Erythema multiforme, skin reaction, pruritus, pruritic rash, urticaria, allergic dermatitis, pemphigoid, sweat discoloration, cutaneous reactions^[Ref]

Endocrine

Isoniazid:

• Frequency not reported: Gynecomastia, hyperglycemia

Rifampin:

• Rare (less than 0.1%): Adrenal insufficiency
• Frequency not reported: Menstrual disorder/disturbances^[Ref]

Gastrointestinal

• Frequency not reported: Nausea, vomiting, epigastric distress, diarrhea

Isoniazid:

• Frequency not reported: Constipation, dry mouth, pancreatitis

Rifampin:

• Frequency not reported: Gastrointestinal disorder, abdominal discomfort, heartburn, flatulence, cramps, pseudomembranous colitis, sore mouth, sore tongue^[Ref]

Hematologic

• Frequency not reported: Thrombocytopenia, eosinophilia, agranulocytosis, hemolytic anemia

Isoniazid:

• Frequency not reported: Anemia, aplastic anemia, lymphadenopathy

Rifampin:

• Uncommon (0.1% to 1%): Leukopenia
• Rare (less than 0.1%): Disseminated intravascular coagulation
• Frequency not reported: Decreased hemoglobin^[Ref]

Hepatic

• Frequency not reported: Hepatitis, elevated serum transaminases (SGOT, SGPT), bilirubinemia, bilirubinuria, jaundice

Rifampin:

• Common (1% to 10%): Elevated alkaline phosphatase
• Rare (less than 0.1%): Abnormal liver function, shock-like syndrome with hepatic involvement
• Frequency not reported: Hyperbilirubinemia^[Ref]

Hypersensitivity

Rifampin:

• Rare (less than 0.1%): Anaphylaxis^[Ref]

Metabolic

Isoniazid:

• Frequency not reported: Pellagra, pyridoxine deficiency, metabolic acidosis

Rifampin:

• Frequency not reported: Decreased appetite, anorexia^[Ref]

Musculoskeletal

Isoniazid:

• Frequency not reported: Systemic lupus erythematosus-like syndrome, rheumatic syndrome

Rifampin:

• Rare (less than 0.1%): Myopathy
• Frequency not reported: Muscle weakness, bone pain^[Ref]

Nervous system

Isoniazid:

• Common (1% to 10%): Peripheral neuropathy
• Uncommon (0.1% to 1%): Convulsions, toxic encephalopathy, optic neuritis and atrophy, memory impairment
• Frequency not reported: Vertigo, polyneuritis (presenting as paresthesia, muscle weakness, loss of tendon reflexes)

Rifampin:

• Frequency not reported: Headache, drowsiness, cerebral hemorrhage, ataxia, dizziness, inability to concentrate, muscular weakness, pains in extremities, generalized numbness^[Ref]

Peripheral neuropathy associated with isoniazid is dose-dependent, most often occurs in malnourished patients and in patients predisposed to neuritis (such as alcoholics and diabetics), and generally follows paresthesias of the hands and feet. The rate is higher in slow acetylators.^[Ref]

Ocular

Rifampin:

• Frequency not reported: Tear discoloration, visual disturbances, conjunctivitis^[Ref]

Other

• Frequency not reported: Fever

Isoniazid:

• Frequency not reported: Anti-nuclear antibodies

Rifampin:

• Frequency not reported: Influenza-like syndrome, post-partum hemorrhage, fetal-maternal hemorrhage, porphyria, edema, fatigue, facial edema, edema of the extremities, shock^[Ref]

Psychiatric

Isoniazid:

• Frequency not reported: Toxic psychosis

Rifampin:

• Frequency not reported: Psychotic disorder/psychoses, mental confusion, behavioral changes^[Ref]

Renal

Rifampin:

• Rare (less than 0.1%): Hemolysis, hemoglobinuria, hematuria, interstitial nephritis, acute tubular necrosis, renal insufficiency, acute renal failure
• Frequency not reported: Acute kidney injury, chromaturia, increased blood creatinine, elevated BUN, elevated serum uric acid^[Ref]

Respiratory

Rifampin:

• Frequency not reported: Dyspnea, wheezing, discolored sputum, shortness of breath^[Ref]

Further information

Rifamate 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.

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