Tuberculosis: Drug Therapy

Key points

• Active pulmonary TB (NICE NG33) — initial phase, first 2 months: Rifampicin + Isoniazid + Pyrazinamide + Ethambutol (RIPE), with pyridoxine alongside isoniazid.
• Continuation phase, next 4 months: rifampicin + isoniazid — a standard 6-month course in total.
• Meningeal (CNS) TB: 12 months of treatment, with adjunctive dexamethasone or prednisolone tapered over 4-8 weeks · do not use ethambutol’s standard duration as a guide here.
• Latent TB: 3 months of isoniazid (with pyridoxine) plus rifampicin, OR 6 months of isoniazid (with pyridoxine) · exclude active disease before treating latent infection.
• Directly observed therapy is no longer routine — offer enhanced case management and DOT to those at risk of poor adherence: homelessness, drug or alcohol misuse, prison history, previous non-adherence, or serious mental illness.
• Check baseline liver function and visual acuity (ethambutol) · warn about rifampicin’s orange secretions and enzyme induction · isoniazid causes peripheral neuropathy, hence pyridoxine.

Decision points in this pathway

• Meningeal or CNS tuberculosis?
• Active disease (as opposed to latent infection)?

The full step-by-step algorithm, including what to do at each branch, opens in the app for approved members.