Ethambutol-induced optic neuritis in a case of pulmonary tuberculosis

Ethambutol hydrochloride (EMB) is one of the integral first-line antitubercular agents used in both intensive and continuation phase as per Revised National Tuberculosis Control Programme guidelines. Although usually well tolerated, reports of ocular toxicity secondary to ethambutol have not been rare. The toxicity is dose and duration dependent, and is reported to be usually reversible if detected early, followed by drug stoppage. The present case discusses ethambutol-induced optic neuritis in a male patient diagnosed with pulmonary tuberculosis.