All patients with bacteriologically confirmed tuberculosis must be treated, and as much as possible treatment should be ambulatory except for clinically seriously ill patients and those with severe complications e.g spontaneous pneumothorax, pleural effusion, massive haemoptysis, etc. who may need to be admitted in the hospital for an initial short period.
The most important drugs for the treatment of tuberculosis are streptomycin (S), Isoniazid (INH or H), rifampicin (R), Pyrazinamide (Z), thiacetazone (TN1 or T), para-amino salysilic acid (PAS) and ethambutol (E).
Other drugs, the second line drugs which can be used in tuberculosis treatment include cycloserine, prothionamide or ethionamide, kanamycin and capromycin.
Treatment with more than one drug (multiple drug therapy-MDT) is necessary to avoid emergence of drug resistance strains and as a result of their different actions the drugs are usually used in a variety of combinations for different durations.
SHORT COURSE CHEMOTHERAPY
This is the chemotherapy for new sputum positive cases (previously treated) and for tuberculosis given for nine months or less, usually eight months, two or three of which are for the intensive phase, and five to six months for the continuation phase of the treatments.
The adult dosages for the commonly used drugs for the short course chemotherapy are:-
- Rifampicin (R): 600mg daily
- Isoniazid (INH): 300mg daily
- Pyrazinomide (Z): 1600mg-2G daily
- Ethambutol (E): 800mg-1200mg daily
- Streptomycin (S): 1G daily (for elderly) patients over 45years 0.75G
The initial intensive phase is designed to kill actively growing and semi-dormant bacilli and if properly taken the chemotherapy at this phase will rapidly reduce the number of micro-organisms and render the patient less, if not non-infectious. Therefore, once the patient has been diagnosed and put on chemotherapy, there is, for all practical purpose, no risk of spreading the infection to close family members. The situation does not however, apply to multi drug resistance tuberculosis or in areas where multi drug resistance is known to be frequent.
The continuation phase aims to eliminate most residual bacilli and since there are low numbers of bacilli following successful intensive phase, fewer drugs are needed in the continuation phase to reduce treatment failure and relapse.