Products
Ethambutol is commercially available in the form of film-coated tablets (Myambutol, combination products). It has been approved in many countries since 1967.
Structure and properties
Ethambutol (C10H24N2O2, Mr = 204.3 g/mol) is present in drugs as ethambutol dihydrochloride, a white, crystalline, hygroscopic powder that is readily soluble in water.
Effects
Ethambutol (ATC J04AK02) has bacteriostatic to bactericidal properties against mycobacteria.
Indications
In combination with other antituberculosis drugs for the treatment of tuberculosis.
Dosage
According to the SmPC. Ethambutol should not be prescribed as monotherapy. The drug is taken once daily and independently of meals. According to the German SmPC, the tablets should be given as a single dose in the morning and fasting.
Contraindications
- Hypersensitivity
- Pre-damaged optic nerve
- Eye diseases
For complete precautions, see the drug label.
Interactions
Antacids (aluminum hydroxide) may reduce the absorption of ethambutol and therefore should not be taken concomitantly. Combination with other neurotoxic drugs such as disulfiram (Antabuse) should be avoided.
Adverse effects
Possible adverse effects include blood count disturbances, psychiatric and central disturbances (eg, dizziness, confusion, hallucinations), digestive disturbances, hepatotoxicity, rash, gout, joint pain, and fever. Ethambutol can inflame and damage the optic nerve and cause visual disturbances, visual field loss, and in the worst cases, blindness. Therefore, close monitoring is indicated.
