Drug information of Rifabutin

Rifabutin


A broad-spectrum antibiotic that is being used as prophylaxis against disseminated Mycobacterium avium complex infection in HIV-positive patients.

Mechanism of effect

Rifabutin acts via the inhibition of DNA-dependent RNA polymerase in gram-positive and some gram-negative bacteria, leading to a suppression of RNA synthesis and cell death.

Pharmacodynamic

Rifabutin is an antibiotic that inhibits DNA-dependent RNA polymerase activity in susceptible cells. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme. It is bactericidal and has a very broad spectrum of activity against most gram-positive and gram-negative organisms (including Pseudomonas aeruginosa) and specifically Mycobacterium tuberculosis.

 Because of rapid emergence of resistant bacteria, use is restricted to treatment of mycobacterial infections and a few other indications. Rifabutin is well absorbed when taken orally and is distributed widely in body tissues and fluids, including the CSF.

Pharmacokinetics

Absorption: readily, 53%

Distribution: body tissues including the lungs, liver, spleen, eyes, & kidneys

Vd: 9.32 L/kg

Protein Bound: 85%

Bioavailability: absolute: HIV: 20%

Half-Life, Elim45 hr (range: 16-69 hr)

Peak Plasma Time: 2-4 hr

Metabolism: hepatic CYP3A4 to active and inactive metabolites

Excretion

Urine: 10% as unchanged drug, 53% as metabolites

Feces: 10% as unchanged drug, 30% as metabolites

Drug indications

tuberculosis

Dosage

Adult

Mycobacterium avium complex Prophylaxis

300 mg PO qDay

Pediatric

Mycobacterium Avium Complex (MAC)

Treatment: 5-10 mg/kg PO qD ; no more than 300 mg/d

Prophylaxis: 1st episode in HIV/recurrence: 5 mg/kg PO qD; no more than 300 mg/d

Interactions

Amlodipine/Atorvastatine , Aripiprazole , Alprazolam , Amiodarone , Aprepitant , Erlotinib , Erythromycin , prednisone , nelfinavir , Prednisolone , Lopinavir , Hydrocodone , lumefantrine , Sofosbuvir , ergotamine , Praziquantel , Quetiapine , Quinidine , Ethinyl Estradiol , Clarithromycin , Colchicine , Clopidogrel , Clozapine , Solifenacin , Daclatasvir , Hydroxy progesteron , Hydrocortisone , Warfarin , Verapamil , Voriconazole , Carbamazepine , Loratadin , Lovastatin , Methadone , Methylprednisolone , Midazolam , Nilotinib , Sildenafil , Cilostazol , Simvastatin , Cinacalcet , Cyclosporine , Fludrocortisone , Dihydroergotamine , Diazepam , Diltiazem , Repaglinide , Sorafenib , Sirolimus , Theophyline , Tacrolimus , Trazodone , Triamcinolone , Tolterodine , Dexamethasone , Steradiol , Estrogen cojugated , Everolimus , Irinotecan , Budesonide , Buspirone , Ranolazine , Stavudine , Axitinib , Almotriptan , ritonavir , saquinavir , eletriptan , Apixaban , brigatinib , Dutasteride , Copanlisib , Tipranavir , Simeprevir , lumacaftor and Ivacaftor , Ulipristal , Etravirine , Dabrafenib , Estropipate , Acalabrutinib , Darifenacin , Nicardipine , Nisoldipine , cobicistat , Delavirdine , Sofosbuvir and velpatasvir , Fostamatinib , Apremilast , Pazopanib , Palbociclib , Tasimelteon , Doravirine , raltegravir , tezacaftor/ivacaftor , Alpelisib , Pitolisant , atovaquone/proguanil , Cabozantinib , ELBASVIR/GRAZOPREVIR , glasdegib , Abemaciclib , Triphasic , Eliglustat , Elvitegravir , Bepridil , bazedoxifene/conjugated estrogens , bedaquiline , Gefitinib , Dasatinib , vemurafenib , Typhoid vaccine (live), oral , Bictegravir , voxelotor , stiripentol , Avapritinib , Netupitant , Capmatinib , Bromazepam , Dienestrol

Alerts

  • Monitor hematologic status
  • Eye pain, redness, loss of vision may indicate inflammatory ocular condition
  • Joint stiffness, swelling, tenderness or paresthesia may indicate arthralgias or myositis
  • May have brown-orange color of urine, feces, saliva, sputum, perspiration, tears, & skin

Points of recommendation

Have blood work checked as you have been told by the doctor. Talk with the doctor.

This medicine may stain contact lenses.

This medicine may change the color of urine, stools, saliva, sweat, tears, and skin to a brown-orange color. This is normal and not harmful.

Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Use some other kind of birth control also like a condom when taking rifabutin.

Take with or without food. Take with food if it causes an upset stomach.

Pregnancy level

B

Related drugs

Rifampin , Capreomycin , Pyrazinamide


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