14.3.2 Phases of chemotherapy
The chemotherapy (drug treatment) of tuberculosis has two phases, known as the intensive and the continuation phases.
The intensive phase consists of four or more drugs for the first eight weeks for new cases, and 12 weeks for re-treatment cases. It makes the patient non-infectious by rapidly reducing the load of bacteria in the sputum, usually within two to three weeks (except in cases of drug resistance). During the intensive phase, the drugs must be collected daily by the patient and must be swallowed under the direct observation (DOTS) of you or another health worker or a treatment supporter.
The continuation phase immediately follows the intensive phase and is important to ensure completion of treatment and a cure; it is essential to avoid relapse after completion of treatment. This phase requires at least two drugs, to be taken for four or six months in the case of Category I and Category III patients, or for five months for Category II patients. During the continuation phase, you should encourage the patient to go and collect the drugs every month — perhaps you can accompany the patient to collect the drugs — and then follow-up to ensure that the patient is taking their medication properly.