Ethomid Special Precautions

Resistance: The use of ethionamide alone in the treatment of tuberculosis results in rapid development of resistance. It is essential, therefore, to give a suitable companion, the choice being based on results of susceptibility testing. However, therapy may be initiated prior to receiving the results of susceptibility tests as deemed appropriate by the physician.
Liver toxicity: Serum AST (SGOT) and ALT (SGPT) concentration should be determined prior to and at monthly intervals during ethionamide therapy. If serum transaminases become elevated during ethionamide therapy, the drug and concomitant antituberculosis agents may be discontinued temporarily until laboratory abnormalities resolve. Ethionamide and concomitant antituberculosis drugs should then be reintroduced sequentially to determine which drug(s) is responsible for the hepatotoxicity.
Neurological effects: Psychotic disturbances, mental depression, restlessness, drowsiness, dizziness, headache, postural hypotension, and asthenia occur occasionally with ethionamide. Rarely, peripheral neuritis, paresthesia, seizures, tremors, a pellagra-like syndrome, hallucinations, diplopia, optic neuritis, blurred vision, and olfactory disturbances have been reported. It recommends concomitant use of pyridoxine to prevent or relieve neurotoxic effects during ethionamide treatment.
Blood glucose: Blood glucose concentrations should be determined prior to and periodically during ethionamide therapy. The management of patients with diabetes mellitus may become more difficult during ethionamide therapy. Diabetic patients should be particularly alert for hypoglycemic episodes.
Hypothyroidism: Thyroid function tests should be monitored periodically (e.g., at baseline and at monthly intervals) since hypothyroidism, with or without goiter, has been reported during ethionamide therapy.
Allergic reactions: Hypersensitivity reactions including rash, photosensitivity, thrombocytopenia, and purpura have been reported rarely with ethionamide.