b. Rifampin (Rifadin). This drug, a semisynthetic derivative of rifamycin, is
given orally and usually well tolerated. The drug distributes readily into all body tissue
fluids including the cerebral spinal fluid (CSF). The dosage is 600 mg (two 300 mg
caps). Rifampin must be used along with another anti-tuberculosis drug. Adverse
reactions include anorexia, diarrhea, and headache.
(1) Drug use. Streptomycin, less effective than isoniazid in advanced
tuberculosis cases, must be given in conjunction with other drugs. The dosage is 1 to 2
mg daily by intramuscular injection.
(2) Adverse reactions. If streptomycin is used daily, the drug may cause
eighth nerve damage (vertigo, deafness). If the drug is continued, the damage may be
irreversible. Occasionally, the patient suffers generalized dermatitis (inflammation of
the skin) in which case use of the drug must be discontinued.
d. Ethambutol (Myambutol).
(1) Drug use. Ethambutol, the principal second line drug, must be used in
combination with another drug, normally isoniazid. Ethambutol will prevent the
development of organisms which are resistant to major drugs. The dosage is 15 mg/kg,
(2) Adverse effects. This drug has few side effects. Optic neuritis
(inflammation of the optic nerve) is one possible side effect, but it is usually minor and
reversible. Before and during treatment with this drug, the patient's clarity of vision
should be checked. If vision becomes less clear, the use of this drug should be
discontinued. Since clearness of vision cannot be properly checked in infants and
young children, avoid using ethambutol with these patients.
e. Bacille Calmette-Guerin Vaccine. Bacille Calmette-Guerin (BCG) vaccine,
administered intradermally, is a living, attenuated strain of tubercle bacilli of bovine origin.
The vaccine offers no positive protection to tuberculin-negative people but can give false-
positive readings. The vaccine converts at least 90 percent of tuberculin-negative
people to a state of skin sensitivity. The protection given by vaccination is only partial,
and no one is quite sure how long the vaccination lasts. Mass vaccination with this
vaccine is applicable only in situations where risk of infection and the number of
tuberculin-negative contacts of active disease are both high.
(1) Drug use. The dosage is 50 mg per day by mouth. Use pyridoxine (B6)
only if the patient experiences side effects when taking isoniazid. This drug is not used
Adverse effects. Adverse effects include irritability or depression.