All India Institute of Medical Sciences, New Delhi
Abstract
Tubercle bacilli readily become resistant to the common
drugs, and resistant bacilli are more likely to proliferate if
they are present in the patient at the start of treatment. So
always use more than one drug. The only possible exception
is prophylaxis for an asymptomatic case with a normal
X-ray.
CAUTION! (1) Never give intermittent (twice or thrice
weekly) treatment unless every dose can be supervised by
a health worker. Daily treatment is usually mandatory.
(2) When you give more than one drug, give them both at the
same time, so that high blood levels coincide; do not give
one drug daily and the other drug less often.
THE DOSES of the commonly used drugs for daily and intermittent
treatment in children and adults are:
lsoniazid (H) 5 mg/kg/24 hours if he is moderately ill and
10 mg/kg/24 hours if he is severely ill. The dose for a twice
weekly course is 15 mg/kg.
CAUTION! Opinions on the dose of isoniazid vary. Some
consider 10 mg/kg/24 hours too much for an Indian child
and always give 5 mg.
Rifampicin (R) 10 mg/kg/24 hours, or 10 mg/kg twice
weekly.
Pyrazinamide (Z) 35 mg/kg/24 hours, 75 mg/kg twice
weekly or 50 mg/kg thrice weekly, is an important drug for
short course treatment, so try to include it whenever it is
mentioned in the regimes below.
Streptomycin (S) 10-20 mg/kg/24 hours, or 40 mg/kg
twice weekly, to a total of not more than 0.75 g. Streptomycin
is painful, so avoid it if you can. If you give it, inject in different
places each day, because repeated injections into the
same site are painful.
Ethambutol (E) 25 mg/kg/24 hours for 2 months, then
15 mg/kg/24 hours. Avoid ethambutol in younger children
(under 12); they are unable to complain of the early
symptoms of retrobulbar neuritis (blindness). Thiacetazone (T) 4 mg/kg/24 hours to a maximum Of
150 mg; unsuitable for intermittent treatment