Rifabutin

A to Z Drug Facts

Rifabutin

	Action
	Indications
	Contraindications
	Route/Dosage
	Interactions
	Lab Test Interferences
	Adverse Reactions
	Precautions
Patient Care Considerations
	Administration/Storage
	Assessment/Interventions
	Patient/Family Education

(RIFF-uh-BYOO-tin)

Mycobutin

Class: Anti-infective/Antitubercular

Action Inhibits DNA-dependent RNA polymerase in susceptible strains of bacteria.

Indications Prevention of disseminated Mycobacterium avium complex (MAC) disease in patients with advanced HIV infection.

Contraindications Hypersensitivity to rifabutin or other rifamycins; active tuberculosis.

Route/Dosage

ADULTS: PO 300 mg once daily. INFANTS AND CHILDREN: PO Up to 5 mg/kg/day.

Interactions

Oral anticoagulants, azole antifungal agents, benzodiazepines, beta-blockers, buspirone, chloramphenicol, clarithromycin, clozapine, oral contraceptives, corticosteroids, cyclosporine, delavirdine, digitoxin, disopyramide, doxycycline, erythromycin, estrogens, haloperidol, hydantoins, indinavir, losartan, methadone, mexiletine, morphine, nelfinavir, ondansetron, quinidine, quinine, ritonavir, sulfonylureas, tacrolimus, tamoxifen, theophyllines, tocainide, toremifene, tricyclic antidepressants, troleandomycin, verapamil, zolpidem: Therapeutic efficacy may be decreased because of liver enzyme-inducing properties of rifabutin. Indinavir, itraconazole, ritonavir: May elevate rifabutin plasma levels, increasing the risk of side effects. Ketoconazole: May reduce rifampin plasma levels, decreasing the therapeutic effects. Zidovudine: May decrease plasma levels of zidovudine.

Lab Test Interferences None well documented.

Adverse Reactions

CV: Chest pain. CNS: Asthenia; headache; insomnia. DERM: Rash. EENT: Taste perversion. GI: Anorexia; diarrhea; dyspepsia; abdominal pain; eructation; flatulence; nausea; vomiting. GU: Discolored urine. HEMA: Anemia; eosinophilia; leukopenia; neutropenia; thrombocytopenia. META: Increased alkaline phosphatase, AST, and ALT. OTHER: Myalgia; fever; discolored saliva, sputum, tears, skin.

Precautions

Pregnancy: Category B. Lactation: Unknown. Discontinue nursing or discontinue drug. Children: Safety and efficacy not established. Based on the limited data available, there is no evidence that doses > 5 mg/kg daily are useful.

PATIENT CARE CONSIDERATIONS

Administration/Storage

Administer on empty stomach. If nausea and vomiting develop, give in divided doses mixed with food such as applesauce.
Store at room temperature, in tightly closed container.

Assessment/Interventions

Obtain patient history, including drug history and any known allergies.
Obtain baseline CBC and monitor at regular intervals during drug therapy. Report decreased neutrophil count.
Inform physician if signs or symptoms of MAC or tuberculosis develops.
Obtain baseline liver function test results and monitor during treatment.

Patient/Family Education

Inform patient that body fluids (eg, urine, feces, saliva, sputum, perspiration, tears) may be brown-orange in color and that soft contact lenses may be permanently stained. Suggest use of glasses during drug therapy.
Instruct patient to use nonhormonal methods of birth control while taking drug.
Instruct patient to notify physician of rash, nausea, vomiting, anorexia, diarrhea, abdominal pain, change in color or consistency of stools, jaundice, arthralgias, myositis, chest pressure or pain with shortness of breath, seizure activity, parathesia, aphasia, confusion, insomnia, excessive fatigue, fever, or infection.
Instruct patient to report photophobia, excessive tearing, or eye pain immediately.