Rifampin

Antibiotic therapy for TB (yearly incidence 2.96:100,000 in USA) and Neisseria meningitidis infection (yearly incidence 0.3:100,000 in USA).

Also used to treat Hansen disease (leprosy) and Legionnaires disease and as prophylaxis against Haemophilus influenzae type B.

Treatment of opioid-induced pruritus associated with the cholestatic jaundice of malignancy

Administered PO or IV

10% of pts receiving rifampin develop chemical hepatitis; 16 deaths per 500,000 receiving drug.

Hepatic dysfunction, most likely in presence of preexisting liver disease and when used in combination with other hepatotoxic agents like isoniazid.

Decreased duration of action of narcotics and barbiturates due to P450 (CYP2D6) enzyme induction.

Pts receiving antiarrhythmic therapy, digoxin, theophylline, phenytoin, or glucocorticoid therapy may need increased doses of these drugs due to enzyme induction.

Complex macrocytic antibiotic approved by FDA in 1971.

Water-soluble at acidic pH; inhibits gram-positive and many gram-negative organisms, incl Escherichia coli , Pseudomonas , Proteus , Klebsiella , Neisseria meningitidis , H. influenzae , Mycobacterium tuberculosis.

Increases in vitro activity of streptomycin and isoniazid.

Primarily eliminated by biliary clearance (30–40%) with up to 30% of the dose excreted in urine.

Half-life 3–5 h; increased with hepatic dysfunction.