Indications

• Staphylococcus Aureus (see Staphylococcus Aureus, [[Staphylococcus Aureus]])
• Leprosy (Hansen’s Disease) (see Leprosy, [[Leprosy]])
• Tuberculosis (see Tuberculosis, [[Tuberculosis]])
  • Active Tuberculosis
  • Latent Tuberculosis (Positive PPD)

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Pharmacology

• Rifamycin Group Antibiotic: inhibits bacterial DNA-dependent RNA polymerase -> inhibits bacterial RNA synthesis
  • Rifamycins (a subclass of the ansamycins) are produced by the bacterium Amycolatopsis Rifamycinica (originally named Streptomyces Mediterranei when it was first isolated in 1957) or synthesized
  • Rifamycins were originally named after the French crime story Rififi (which was favored by the researchers who discovered these agents)
  • Members of Rifamycin Group
    • Rifamycins
    • Rifabutin (see Rifabutin, [[Rifabutin]])
    • Rifalazil
    • Rifampin (Rifampicin)
    • Rifapentine

Metabolism

• xxx

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Administration

• PO: xxx
• IV: xxx

Dose Adjustment

• Hepatic
• Renal

Breast Feeding

• Rifampin is Excreted in Breast Milk: breast feeding should be avoided during rifampin administration

Drug Interactions

• Upregulation of Hepatic Cytochrome P450 Enzymes (CYP2C9, CYP3A4)
  • Increased Coumadin Metabolism (see Coumadin, [[Coumadin]]): decreasing efficacy of coumadin anticoagulation
  • Increased Oral Contraceptive Hormonal Metabolism (see Oral Contraceptives, [[Oral Contraceptives]]): decreasing efficacy

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Adverse Effects

Constitutional Adverse Effects

• Flu-Like Symptoms: may be due to excellent penetration of drug into the brain
  • Fever/Chills (see Fever, [[Fever]])
  • Headache (see Headache, [[Headache]])
  • Arthralgias (see Arthralgias, [[Arthralgias]])
  • Malaise

Dermatologic Adverse Effects

• Flushing (see Flushing, [[Flushing]])
• Pruritus (see Pruritus, [[Pruritus]])
• Rash

Gastrointestinal Adverse Effects

Hepatotoxicity

• Elevated Liver Function Tests (LFT’s) (see Drug-Induced Hepatotoxicity, [[Drug-Induced Hepatotoxicity]])
• Hepatitis (see Drug-Induced Hepatotoxicity, [[Drug-Induced Hepatotoxicity]])
• Hepatic Failure (see Drug-Induced Hepatotoxicity, [[Drug-Induced Hepatotoxicity]])

Other Gastrointetsinal Manifestations

• Abdominal Cramps (see Abdominal Pain, [[Abdominal Pain]])
• Diarrhea (see Diarrhea, [[Diarrhea]])
• Nausea/Vomiting (see Nausea and Vomiting, [[Nausea and Vomiting]])

Pulmonary Adverse Effects

Drug-Induced Pulmonary Eosinophilia (see Drug-Induced Pulmonary Eosinophilia, [[Drug-Induced Pulmonary Eosinophilia]])

• Epidemiology
• Clinical

Dyspnea (see Dyspnea, [[Dyspnea]])

• xxx

Other Adverse Effects

• Orange-Red Secretions/Tears: may stain contact lenses
• Orange-Red Urine (see Urine Discoloration, [[Urine Discoloration]])

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References

• xxx