Rifabutin Dosage

Medically reviewed by Drugs.com. Last updated on Feb 17, 2025.

Usual Adult Dose for Mycobacterium avium-intracellulare - Prophylaxis

300 mg orally once a day

• If prone to nausea, vomiting, or other gastrointestinal upset: 150 mg orally twice a day with food may be useful

Use: For the prevention of disseminated Mycobacterium avium complex (MAC) disease in patients with advanced HIV infection

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations: 300 mg orally once a day

Comments:

• Recommended as alternative therapy to prevent first episode of disseminated MAC disease (primary prophylaxis) in patients who cannot tolerate azithromycin or clarithromycin
• Primary prophylaxis is not recommended for patients who immediately begin antiretroviral therapy (ART).
• Indications for primary prophylaxis:
• CD4 count less than 50 cells/mm3 AND not receiving ART or remains viremic on ART or has no options for fully suppressive ART regimen
• Before starting, disseminated MAC disease should be ruled out by clinical assessment and (if appropriate) by obtaining a blood culture for MAC; if blood culture is obtained, delay prophylaxis until results are available.
• When used with some antiretroviral drugs, dose adjustment of this drug may be required; with certain antiretroviral drugs, this drug is not recommended.
• Active tuberculosis (TB) should be ruled out before starting this drug.
• Current guidelines should be consulted for additional information.

Usual Adult Dose for Atypical Mycobacterial Disease

American Thoracic Society (ATS), European Respiratory Society (ERS), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Infectious Diseases Society of America (IDSA) Recommendations:
MAC:

• Cavitary and refractory: 300 mg/day orally
• Nodular-bronchiectatic: 300 mg orally 3 times a week

M kansasii: 300 mg/day orally OR 300 mg orally 3 times a week
M xenopi: 300 mg/day orally

When used with clarithromycin:

• MAC (cavitary and refractory), M kansasii, and M xenopi: 150 mg/day orally

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations: 300 mg orally once a day

Comments:

• Current guidelines should be consulted for additional information.

ATS, ERS, ESCMID, and IDSA recommendations:

• In combination with 2 or more drugs, recommended as part of preferred regimens for MAC, M kansasii, and M xenopi pulmonary disease
• Monitoring recommendations include liver function test, CBC, visual acuity, and clinical monitoring.

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV recommendations:

• Preferred therapy includes at least 2 drugs as initial therapy to treat disseminated MAC disease; some experts would add rifabutin when signs/symptoms of more severe disease are present.
• Dose adjustment may be needed based on drug interactions.

Usual Adult Dose for Mycobacterium avium-intracellulare - Treatment

American Thoracic Society (ATS), European Respiratory Society (ERS), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Infectious Diseases Society of America (IDSA) Recommendations:
MAC:

• Cavitary and refractory: 300 mg/day orally
• Nodular-bronchiectatic: 300 mg orally 3 times a week

M kansasii: 300 mg/day orally OR 300 mg orally 3 times a week
M xenopi: 300 mg/day orally

When used with clarithromycin:

• MAC (cavitary and refractory), M kansasii, and M xenopi: 150 mg/day orally

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations: 300 mg orally once a day

Comments:

• Current guidelines should be consulted for additional information.

ATS, ERS, ESCMID, and IDSA recommendations:

• In combination with 2 or more drugs, recommended as part of preferred regimens for MAC, M kansasii, and M xenopi pulmonary disease
• Monitoring recommendations include liver function test, CBC, visual acuity, and clinical monitoring.

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV recommendations:

• Preferred therapy includes at least 2 drugs as initial therapy to treat disseminated MAC disease; some experts would add rifabutin when signs/symptoms of more severe disease are present.
• Dose adjustment may be needed based on drug interactions.

Usual Adult Dose for Mycobacterium kansasii

American Thoracic Society (ATS), European Respiratory Society (ERS), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Infectious Diseases Society of America (IDSA) Recommendations:
MAC:

• Cavitary and refractory: 300 mg/day orally
• Nodular-bronchiectatic: 300 mg orally 3 times a week

M kansasii: 300 mg/day orally OR 300 mg orally 3 times a week
M xenopi: 300 mg/day orally

When used with clarithromycin:

• MAC (cavitary and refractory), M kansasii, and M xenopi: 150 mg/day orally

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations: 300 mg orally once a day

Comments:

• Current guidelines should be consulted for additional information.

ATS, ERS, ESCMID, and IDSA recommendations:

• In combination with 2 or more drugs, recommended as part of preferred regimens for MAC, M kansasii, and M xenopi pulmonary disease
• Monitoring recommendations include liver function test, CBC, visual acuity, and clinical monitoring.

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV recommendations:

• Preferred therapy includes at least 2 drugs as initial therapy to treat disseminated MAC disease; some experts would add rifabutin when signs/symptoms of more severe disease are present.
• Dose adjustment may be needed based on drug interactions.

Usual Adult Dose for Tuberculosis - Active

ATS, US CDC, and IDSA Recommendations: 5 mg/kg orally once a day

• Typical dose: 300 mg orally once a day

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations:
For Treatment of Active Drug-Sensitive TB:

• With NRTIs (use tenofovir alafenamide with caution); etravirine (without boosted protease inhibitors); doravirine and oral rilpivirine (dose adjustments needed with rifabutin); dolutegravir, raltegravir; maraviroc (without a strong CYP450 3A4 inhibitor); ibalizumab, enfuvirtide, fostemsavir: 5 mg/kg orally once a day
• Typical dose: 300 mg orally once a day
• With ritonavir-boosted protease inhibitors; maraviroc (with a strong CYP450 3A4 inhibitor): 150 mg orally once a day
• With efavirenz: 450 to 600 mg orally once a day
• With etravirine (with boosted protease inhibitors); bictegravir, elvitegravir/cobicistat; cabotegravir-rilpivirine (IM/oral); protease inhibitors with cobicistat; lenacapavir (oral/subcutaneous): Not recommended

Comments:

• Current guidelines should be consulted for additional information.

ATS, US CDC, and IDSA recommendations:

• Recommended as a first-line drug for TB
• Patients who are not obese may be dosed based on actual weight; for obese patients (more than 20% above ideal body weight [IBW]), dosing based on IBW may be preferred for initial doses.
• Some clinicians prefer a modified IBW (IBW + [0.40 x (actual weight - IBW)]), as is done for initial aminoglycoside doses.
• Because TB drug dosing has not been established for obese patients, therapeutic drug monitoring may be considered for such patients.
• When coadministered with protease inhibitors or NNRTIs, rifabutin dose may need to be adjusted.

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV recommendations:

• Recommended as a component of preferred therapy for drug-susceptible TB during the intensive and continuation phases
• Recommended as a component for isoniazid-resistant TB

Usual Pediatric Dose for Mycobacterium avium-intracellulare - Prophylaxis

Panel on Opportunistic Infections in Children With and Exposed to HIV Recommendations:
Children older than 5 years:

• Primary prophylaxis: 300 mg orally once a day with food
• Secondary prophylaxis: 5 mg/kg orally once a day with food
• Maximum dose: 300 mg/day

Comments:

• Recommended as an alternative agent for primary prophylaxis of MAC
• Primary prophylaxis is indicated for children 6 years and older with CD4 count less than 50 cells/mm3.
• Recommended as a first choice or an alternative agent for secondary prophylaxis (chronic suppressive therapy) of MAC in patients who received this drug as part of initial therapy
• Secondary prophylaxis is indicated in patients with prior disease.
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Mycobacterium avium-intracellulare - Treatment

Panel on Opportunistic Infections in Children With and Exposed to HIV Recommendations: 10 to 20 mg/kg orally once a day

• Maximum dose: 300 mg/day

Comments:

• Recommended as an addition to initial treatment (at least 2 drugs) for severe MAC disease
• Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Tuberculosis - Active

ATS, US CDC, and IDSA Recommendations:

• Children younger than 15 years and weight up to 40 kg: Appropriate dosing is unknown; estimated at 5 mg/kg orally once a day
• Age 15 years and older or weight greater than 40 kg in younger children: 5 mg/kg orally once a day
• Typical dose: 300 mg orally once a day

Panel on Opportunistic Infections in Children With and Exposed to HIV Recommendations: 10 to 20 mg/kg orally once a day OR 3 times a week

• Maximum dose: 300 mg/day

Comments:

• Current guidelines should be consulted for additional information.

ATS, US CDC, and IDSA recommendations:

• Recommended as a first-line drug for TB
• Patients who are not obese may be dosed based on actual weight; for obese patients (more than 20% above IBW), dosing based on IBW may be preferred for initial doses.
• Some clinicians prefer a modified IBW (IBW + [0.40 x (actual weight - IBW)]), as is done for initial aminoglycoside doses.
• Because TB drug dosing has not been established for obese patients, therapeutic drug monitoring may be considered for such patients.

Panel on Opportunistic Infections in Children With and Exposed to HIV recommendations:

• Recommended as an alternative for rifampin for the treatment of TB disease
• Discussion with an expert is recommended.
• Treatment for TB should be provided by directly observed therapy.
• Potential drug toxicity and interactions should be reviewed at each visit.

Renal Dose Adjustments

Mild or moderate renal dysfunction (CrCl 30 to 61 mL/min): No adjustment recommended
Severe renal dysfunction (CrCl less than 30 mL/min): Consider reducing the dose by 50% if toxicity is suspected.

ATS, ERS, ESCMID, and IDSA Recommendations:

• CrCl less than 30 mL/min: Reduce dose by 50%.

Panel on Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV Recommendations:

• CrCl less than 30 mL/min: Consider 50% of dose orally once a day if toxicity is suspected and perform therapeutic drug monitoring.

Liver Dose Adjustments

Mild liver dysfunction: No adjustment recommended
Moderate or severe liver dysfunction: Data not available

ATS, ERS, ESCMID, and IDSA Recommendations: Caution recommended.

Dose Adjustments

Dose reduction may be needed for patients receiving concomitant treatment with certain other drugs.

• In some cases, the dosage of this drug may need to be reduced when coadministered with CYP450 3A inhibitors.
• Coadministration with protease inhibitors may require at least 50% reduction in rifabutin dose, and depending on protease inhibitor, adjustment of the antiretroviral dose; increase monitoring for adverse reactions during coadministration.
• The manufacturer product information should be consulted.

Rifabutin Interaction Studies:
Recommendation when coadministered with:

• Amprenavir: Reduce rifabutin dose by at least 50%; monitor closely for adverse reactions.
• Bictegravir or rilpivirine: Coadministration with bictegravir/emtricitabine/tenofovir or emtricitabine/rilpivirine/tenofovir alafenamide is not recommended; consult the manufacturer product information for these combination drugs for additional information.
• Clarithromycin or fluconazole: Monitor for rifabutin-associated adverse reactions; reduce dose or suspend use of rifabutin if toxicity is suspected.
• Clarithromycin: An alternative for clarithromycin should be considered for patients receiving rifabutin.
• Doravirine: If coadministration is required, increase the doravirine dosage as directed in the manufacturer product information for the doravirine-containing product.
• Indinavir: Reduce rifabutin dose by 50% and increase indinavir dose to 1000 mg 3 times a day.
• Itraconazole or posaconazole: If coadministration cannot be avoided, monitor patients for rifabutin-associated adverse reactions and lack of antifungal efficacy.
• Nelfinavir: Reduce rifabutin dose by 50% (to 150 mg once a day) and increase nelfinavir dose to 1250 mg twice a day.
• Ritonavir-boosted fosamprenavir, lopinavir, saquinavir, or tipranavir: Reduce rifabutin dose by at least 75% (to a maximum 150 mg every other day or 3 times a week).
• Lopinavir-ritonavir OR tipranavir plus ritonavir: Monitor closely for adverse reactions; reduce rifabutin dosage further, as needed.
• Saquinavir plus ritonavir: Monitor closely for adverse reactions.

Precautions

CONTRAINDICATIONS:

• Clinically significant hypersensitivity to the active component or to any other rifamycins
• Coadministration with delavirdine or voriconazole

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• For patients prone to nausea, vomiting, or other gastrointestinal upset, administration with food may be useful.
• Pediatric use: Doses of this drug may be administered mixed with foods such as applesauce.

Storage requirements:

• Keep container tightly closed.
• Store at 25C (77F); excursions permitted to 15C to 30C (59F to 86F).

Monitoring:

• Hematologic: Hematologic studies (periodically)
• Hypersensitivity: For signs/symptoms of hypersensitivity reactions
• Ocular: For uveitis (when used with macrolides or triazole antifungals)

Patient advice:

• Contact your physicians if new signs/symptoms consistent with MAC or tuberculosis develop.
• Notify your physicians if signs/symptoms suggesting myositis or uveitis develop.
• Urine, feces, saliva, sputum, perspiration, tears, and skin may be colored brown-orange with this drug; soft contact lenses may be permanently stained.
• Contact your physician immediately if watery and bloody stools (with or without stomach cramps and fever) develop, even if 2 months or more have elapsed since the last dose of this drug.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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