Back to Infections Drug Index

Back to Antitubercular Agents

Name: Rifampin

Pregnancy Category C

Drug classes

  • Antituberculous drug ("first-line")
  • Antibiotic

Mechanisms of action

Inhibits DNA-dependent RNA polymerase activity in susceptible bacterial cells.


  1. Treatment of pulmonary tuberculosis in conjunction with at least one other effective antituberculous drug
  2. Neisseria meningitidis carriers, for asymptomatic carriers to eliminate meningococci from nasopharynx; not for treatment of meningitis
  3. Unlabeled uses: infections caused by Staphylococcus aureus and Staphylococcus epidermis, usually in combination therapy; gram-negative bacteremia in infancy; Legionella (Legionella pneumophilia), not responsive to erythromycin; leprosy (in combination with dapsone); prophylaxis of meningitis due to Haemophilus influenzae


  • Contraindicated in the presence of allergy to any rifamycin, acute hepatic disease, nursing a baby.
  • Use caution in pregnancy (teratogenic effects have been reported in preclinical studies; safest antituberculous regimen for use in pregnancy is considered to be rifampin, isoniazid, and ethambutol).

Adverse effects

  • CNS: Headache, drowsiness, fatigue, dizziness, inability to concentrate, mental confusion, generalized numbness, ataxia, muscle weakness, visual disturbances, exudative conjunctivitis
  • GI: Heartburn, epigastric distress, anorexia, nausea, vomiting, gas, cramps, diarrhea, pseudomembranous colitis, pancreatitis, elevations of liver enzymes, hepatitis
  • Hematologic: Eosinophilia, thrombocytopenia, transient leukopenia, hemolytic anemia, decreased hemoglobin, hemolysis
  • GU: Hemoglobinuria, hematuria, renal insufficiency, acute renal failure, menstrual disturbances
  • Dermatologic: Rash, pruritus, urticaria, pemphigoid reaction, flushing, reddish-orange discoloration of body fluids-tears, saliva, urine, sweat, sputum
  • Other: Pain in extremities, osteomalacia, myopathy, fever, "flulike" syndrome

Are you a Doctor, Pharmacist, PA or a Nurse?

Join the Doctors Lounge online medical community

  • Editorial activities: Publish, peer review, edit online articles.

  • Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.

Doctors Lounge Membership Application

Tools & Services: Follow DoctorsLounge on Twitter Follow us on Twitter | RSS News | Newsletter | Contact us