Acute Psychosis after Recent Isoniazid Initiation.

Isoniazid as part of Directly Observed Treatment-Short course (DOTS) regimen is universally used. Although, associated psychosis in certain cases is documented earlier, type of symptoms and onset of symptoms remains highly variable. We describe a case of 54-year-old female on anti-tubercular therapy with onset of psychosis within three days of Isoniazid initiation characterised by agitation, loosening of association, echolalia with spontaneous remission after drug stoppage. This case highlights the importance of remaining vigilant and considering isoniazid as possible causative agent for psychosis even within days of its intiation and avoiding delay in management.