A Case of Delusional Disorder With Abuse of Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol, the First-Line Anti-tuberculosis Therapy Drugs in India.

Tuberculosis (TB) and mental illnesses frequently coexist and are both extremely common worldwide. Through the National Program for Elimination of Tuberculosis (NTEP), anti-tuberculosis therapy (ATT) medications are used to treat tuberculosis in India. We want to report a case 45-year-old patient from the state of Andhra Pradesh, India with comorbid delusional disorder leading to daily ATT drug consumption for the past 20 years. This unusual presentation demonstrates that abuse of a Schedule "H" substance like ATT is also conceivable. To stop "Off-label" purchases, strict measures must be taken. Before beginning ATT, evaluating the patient's mental health may be a wise move.