What it does
Rifabutin is an antibiotic used to treat certain bacterial infections, particularly those caused by mycobacteria.
Commonly used for: tuberculosis (TB), mycobacterial infections
Read more in plain English ↓Plain-language summary for general understanding - not medical advice. Always follow your pharmacist/doctor.
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Source: Pharmacy and Poisons Board · fetched 2026-01-28 21:30:38 · updated 2026-07-20 11:04:47
Drug Interactions
28Severe (10)
Antifungals,azoles - decreases exposure
Rifabutin is predicted to decrease the exposure to antifungals, azoles (isavuconazole). Avoid.
Antimalarials - decreases exposure
Rifabutins lightly decreases the exposure to antimalarials (atovaquone). Avoid.
Atovaquone - decreases exposure
Rifabutins lightly decreases the exposure to antimalarials (atovaquone). Avoid.
Bictegravir - decreases exposure
Rifabutins lightly decreases the exposure to bictegravir. Avoid.
Cabazitaxel - decreases exposure
Rifabutinispredictedtodecreasetheexposuretotaxanes (cabazitaxel).Avoid.oTheoretical
Isavuconazole - decreases exposure
Rifabutin is predicted to decrease the exposure to antifungals, azoles (isavuconazole). Avoid.
Mobocertinib - decreases exposure
Rifabutinispredictedtodecreasetheexposureto mobocertinib.Avoid.rTheoretical
Rifabutin - increases concentration
Ketoconazole is predicted to increase the concentration of rifamycins (rifabutin) and rifamycins (rifabutin) are predicted to decrease the concentration of ketoconazole. Avoid.
Taxanes - decreases exposure
Rifabutinispredictedtodecreasetheexposuretotaxanes (cabazitaxel).Avoid.oTheoretical
Voxilaprevir - decreases concentration
Rifabutinispredictedtodecreasetheconcentrationof voxilaprevir.Avoid.rTheoretical
Moderate (10)
Clarithromycin - decreases concentration
Rifabutin decreases the concentration of macrolides (clarithromycin) and macrolides (clarithromycin) increase the concentration of rifabutin. Monitor and adjust dose.
Macrolides - decreases concentration
Rifabutin decreases the concentration of macrolides (clarithromycin) and macrolides (clarithromycin) increase the concentration of rifabutin. Monitor and adjust dose.
Pralsetinib - decreases exposure
Rifabutin is predicted to decrease the exposure to pralsetinib. Avoid or adjust dose-consult product literature.
Rifabutin - increases risk of uveitis
Fluconazole increases the risk of uveitis when given with rifamycins (rifabutin). Adjust dose.
Rifabutin - increases concentration
Miconazole is predicted to increase the concentration of rifamycins (rifabutin). Use with caution and adjust dose.
Rifabutin - increases exposure
Rifamycins (rifabutin) decrease the concentration of cobicistat and cobicistat increases the exposure to rifamycins (rifabutin). Avoid or adjust dose.
Rifabutin - increases exposure
Ritonavir markedly increases the exposure to rifamycins (rifabutin). Avoid or adjust dose.
Rifabutin - decreases exposure
Lumacaftor is predicted to decrease the exposure to rifamycins (rifabutin). Adjust dose.
Rifabutin - increases concentration
Erythromycin is predicted to increase the concentration of rifamycins (rifabutin) and rifamycins (rifabutin) are predicted to decrease the concentration of erythromycin. Monitor and adjust dose.
Rifabutin - decreases exposure
Efavirenz slightly decreases the exposure to rifamycins (rifabutin). Adjust dose.
Unknown (8)
Antifungals,azoles - decreases concentration
Rifabutin decreases the concentration of antifungals, azoles (voriconazole) and antifungals, azoles (voriconazole) increase the concentration of rifabutin. Avoid or adjust voriconazole dose, p. 662.
Cobicistat And Cobicistat Increases The Exposure To Rifabutin - decreases concentration
Rifabutin decreases the concentration of cobicistat and cobicistat increases the exposure to rifabutin. Avoid or adjust dose.
Coumarins - decreases anticoagulant effect
Rifabutinmightdecreasetheanticoagulanteffectof coumarins.oTheoretical
Elexacaftor - decreases exposure
Rifabutinispredictedtodecreasetheexposuretoelexacaftor. Avoid.rTheoretical
Ledipasvir - decreases exposure
Rifabutinispredictedtodecreasetheexposuretoledipasvir. Avoid.rTheoretical
Letermovir - decreases concentration
Rifabutinispredictedtodecreasetheconcentrationof letermovir.oTheoretical
Rifabutin - increases concentration
Rifamycins (rifabutin) decrease the concentration of voriconazole and voriconazole increases the concentration of rifamycins (rifabutin). Avoid or adjust voriconazole dose, p. 662.
Voriconazole - decreases concentration
Rifabutin decreases the concentration of antifungals, azoles (voriconazole) and antifungals, azoles (voriconazole) increase the concentration of rifabutin. Avoid or adjust voriconazole dose, p. 662.
Data from BNF 85 (British National Formulary). This is not a substitute for professional medical advice. Matched via: exact
About this medicine
Rifabutin is an antibiotic used to treat certain bacterial infections, particularly those caused by mycobacteria.
What it treats
- tuberculosis (TB)
- mycobacterial infections
How it works
Rifabutin works by stopping the growth of bacteria that cause infections.
Who it's for
It is generally used for people with specific bacterial infections, especially those with weakened immune systems.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
Clinical monograph: Rifabutin
BNF-referencedRifabutin is an antimycobacterial agent primarily used for the prophylaxis and treatment of infections caused by Mycobacterium avium complex in immunocompromised patients, and for the treatment of pulmonary tuberculosis in combination with other antitubercular drugs. It belongs to the rifamycin class and is known for its ability to penetrate macrophages and intracellular sites of infection.
Indications
- Prophylaxis of Mycobacterium avium complex infections in immunosuppressed patients with low CD4 count
- Treatment of non-tuberculous mycobacterial disease, in combination with other drugs
- Treatment of pulmonary tuberculosis, in combination with other drugs
- Helicobacter pylori eradication (unlicensed use)
Dosage
Children: Child 12–17 years: 450–600 mg once daily for up to 6 months after cultures negative. For children under 12 years, rifabutin is not licensed for use.
Adults: 300 mg once daily for prophylaxis of Mycobacterium avium complex infections. For treatment of pulmonary tuberculosis, the dosage ranges from 150-450 mg once daily for at least 6 months, depending on the treatment regimen.
Mechanism of action
Rifabutin exerts its antibacterial effect by inhibiting bacterial DNA-dependent RNA polymerase, which is essential for RNA synthesis in bacteria. This action ultimately disrupts protein synthesis, leading to bacterial cell death. It is particularly effective against mycobacteria, including those resistant to other antibiotics.
Pharmacodynamics
Rifabutin demonstrates concentration-dependent killing, meaning higher drug concentrations can lead to more effective bacterial eradication. The drug is effective against a variety of mycobacterial species, including those that cause tuberculosis and non-tuberculous mycobacterial infections.
Pharmacokinetics
Rifabutin is well absorbed from the gastrointestinal tract, with bioavailability ranging between 20% and 60%. It undergoes extensive hepatic metabolism primarily via the cytochrome P450 system, particularly CYP3A4. The elimination half-life is approximately 35 hours, allowing for once-daily dosing. It is excreted mainly in the urine and bile, and dosage adjustments may be necessary in patients with hepatic impairment.
Contra-indications
- Hypersensitivity to rifabutin or any component of the formulation
- Acute porphyrias
- Intestinal obstruction
Adverse effects
- Granulocytosis
- Anaemia
- Arthralgia
- Bronchospasm
- Chest pain
- Corneal deposits
- Decreased leucocytes
- Dyspnoea
- Eosinophilia
- Fever
- Haemolysis
- Neutropenia
- Pancytopenia
- Skin reactions
- Thrombocytopenia
- Urine discoloration
- Uveitis
- Memory loss
- Muscle weakness
- Palpitations
- Seizures
- Taste alterations
- Nasal disorders
- Dry mouth
- Throat pain
- Hot flushes
- Increased risk of infection
Interactions
- Ketoconazole: Severe (increases concentration)
- Antifungals, azoles: Severe (decreases exposure)
- Isavuconazole: Severe (decreases exposure)
- Antimalarials: Severe (decreases exposure)
- Atovaquone: Severe (decreases exposure)
- Bictegravir: Severe (decreases exposure)
- Mobocertinib: Severe (decreases exposure)
- Taxanes: Severe (decreases exposure)
- Cabazitaxel: Severe (decreases exposure)
- Voxilaprevir: Severe (decreases concentration)
Precautions
- Use caution in patients with hepatic impairment
- Monitor for signs of liver disorder
- May discolor soft contact lenses
- Gradually re-introduce after treatment interruption
- Regular blood tests to monitor for blood dyscrasias
Pregnancy
Manufacturer advises caution; limited data on safety in pregnancy.
Breast-feeding
Manufacturer advises avoiding use; no information available on excretion in breast milk.
Storage
Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.
Formulations
- Capsules: 150 mg
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Molecular reference: Rifabutin
PubChem CID 135415564Molecular formula: C46H62N4O11
Source: PubChem (NCBI) · pathways from PathBank, Reactome, WikiPathways & PharmGKB.
This drug in other countries
The same active ingredient registered across other registries we cover - including different brands.