Used primarily in the treatment of tuberculosis, especially multidrug-resistant tuberculosis (MDR-TB). It works by inhibiting the synthesis of mycolic acids, which are essential components of the mycobacterial cell wall. Typically administered orally, it is part of a combination therapy regimen to prevent the development of further resistance. Due to its potential for hepatotoxicity and gastrointestinal side effects, liver function is monitored during treatment. Often reserved for cases where first-line drugs are ineffective or cannot be used.