Medicine & USMLE


Anti-Infective Drugs
  1. Vancomycin
  2. Metronidazole
  3. Penicillins
  4. Cephalosporins
  5. Macrolides
  6. Fluoroquinolones
  7. Aminoglycosides
  8. Tetracyclines
  9. Sulfonamides
  10. Rifampin
  11. Isoniazid
  12. Ethambutol
  13. Chloroquine
  14. Acyclovir
  15. Oseltamivir
  16. Azoles
  17. Nystatin
  18. Amphotericin B


Ethambutol is a medication used to treat tuberculosis. It’s main adverse effect is ocular toxicity, so it’s important for patients to receive frequent eye exams and notify their provider if they notice any vision changes.

Key Points

  • Ethambutol
    • Mechanism
      • Antitubercular
        • Used in combination with other antitubercular agents
    • Clinical Uses
      • Tuberculosis
        • Used as one of the 4-drug RIPE combination regimen for active tuberculosis: rifampin, isoniazid, pyrazinamide, and ethambutol
    • Side Effects and Adverse Reactions
      • Ocular (Eye) Toxicity
        • Can lead to optic neuritis, manifesting with blurred vision, loss of color (red-green) distinction, and decreased visual acuity
        • Reversed by discontinuation of the drug
        • Patient should receive frequent eye exams
      • Dizziness, confusion, hallucinations
      • Joint pain
      • **Note: other antitubercular drugs cause hepatotoxicity, but ethambutol does not