Rifamycin
Rifamycins bind to and inhibit DNA-dependant RNA polymerase
Most likely concentration dependent killing (peak:MIC)
Cmax: 0.2-0.6mg/L; Tmax: 2.5-4 hours; Bioavailability: 20%; Protein binding: 71-85%; Table 3
Hepatic: hepatotoxicity, jaundice, hepatitis
Hematologic: Thrombocytopenia, hemolytic anemia
Musculo-skeletal: Arthralgias
Skin: Rash
GI: Nausea, vomiting, loss of appetite
Kidneys: Acute renal failure, interstitial nephritis,
Other: shock, flu-like syndrome (at least with related rifampin), body fluid discoloration (tears, sweat may be orange colored)
Precautions: Hepatic impairment
Due to its known induction of P450 liver isoenzymes, caution should be exercised when administering this agent with other drugs metabolized in the liver. Please see the the “Drug Interactions” section in the text/website for a complete list of relevant interactions. Heparin may negate the action of rifabutin.
Category B: No evidence of risk in humans but studies inadequate
Toxic: baseline liver function tests, bilirubin, serum creatinine, complete blood count and platelet count.
Rifabutin (Various manufacturers worldwide)
Alfacid - Grunenthal, Germany
Ansamycin - Adria Laboratories
Ansatipine - Pharmacia, France
Ansatipin - Kenfarma, Spain, Finland
Mycobutin - Pharmacia , USA, Greece, Canada, Netherlands, Portugal, Switzerland, Australia, Austria, Belgium, Czech Republic, Germany, Hong Kong, Israel, Italy, New Zealand, South Africa, United Kingdom, Greece