TB treatment and common side effects

Initial phase (2 months):
- Isoniazid (INH)
Can cause hepatotoxicity and peripheral neuropathy (give with Vitamin B6, especially in patients at risk for neuropathy - diabetics, alcoholics, HIV, pregnant)
- Rifampin (RIF)
Excreted as a red-orange compound in urine, tears, sweat, and stool
Can cause hepatotoxicity (less common than with INH)
Induces hepatic microsomal enzymes and may increase hepatic clearance of other drugs
- Pyrazinamide
Commonly causes GI upset
Can cause hepatotoxicity and hyperuricemia (can induce gout flares in patient's at risk)
- Ethambutol
Can cause hepatotoxicity and optic neuritis (screen monthly for visual disturbances)


Continuation phase (4 or 7 months):
- INH
- RIF


Follow-up:
- Repeat sputum smear and culture two months after initiation of therapy
- Liver panel