Abstract
The revised World Health Organization guidelines on multidrug-resistant tuberculosis include linezolid in the core drugs group. Consequently, the use of linezolid for patients with multidrug-resistant tuberculosis is increasing. Common adverse events of long-term linezolid use include bone marrow suppression and neuropathies. However, there is limited information on a rare adverse event, black hairy tongue. Here, we report a case of linezolid-induced black hairy tongue in a patient with multidrug-resistant tuberculosis. The etiology, pathogenesis, diagnosis, and treatment of black hairy tongue are also discussed.