Generic Name: Rifabutin Brand Name(s): Generics only. No brands available.

Uses

What is Rifabutin used for?

Rifabutin is used alone or with another medication to help prevent a certain serious infection (Mycobacterium avium complex-MAC). Rifabutin is known as a rifamycin antibiotic. It works by stopping the growth of bacteria.

This antibiotic treats and prevents only bacterial infections. It will not work for viral infections (such as common cold, flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness.

How should I take Rifabutin?

Take this medication by mouth with or without food, usually once or twice daily or as directed by your doctor. Take this medication with food if stomach upset occurs. For the treatment of tuberculosis, this drug is sometimes taken twice weekly.

Dosage is based on your medical condition, weight, interacting drugs, and response to treatment.

For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.

Continue to take this medication until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may allow the bacteria to continue to grow, which may result in a return of the infection and cause the infection to be more difficult to treat (resistant).

Tell your doctor if your condition persists or worsens.

How do I store Rifabutin?

Rifabutin is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Rifabutin in the bathroom or the freezer. There may be different brands of Rifabutin that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Rifabutin down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Rifabutin?

Before taking rifabutin, tell your doctor or pharmacist if you are allergic to it; or to other rifamycins (such as rifampin); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, liver disease, a certain blood disorder (porphyria).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Rifabutin may cause live bacterial vaccines (such as typhoid vaccine) to not work as well. Do not have any immunizations/vaccinations while using this medication unless your doctor tells you to.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Discuss the risks and benefits with your doctor before breast-feeding. If you have HIV disease, do not breast-feed because breast milk can transmit HIV.

Is it safe during pregnancy or breast-feeding?

There are no adequate studies in women for determining risk when using this Rifabutin during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Rifabutin. Rifabutin is pregnancy risk category B according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk,
  • B=No risk in some studies,
  • C=There may be some risk,
  • D=Positive evidence of risk,
  • X=Contraindicated,
  • N=Unknown

Side effects

What side effects can occur from Rifabutin?

Diarrhea, stomach upset, changes in taste, or nausea/vomiting may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

This medication may cause urine, sweat, saliva, or tears to turn brown-orange. This effect is harmless and will disappear when the medication is stopped. However, dentures and contact lenses may be permanently stained.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if any of these rare but seriouseasy bleeding/bruising, signs of a new infection (such as fever, persistent sore throat/cough), muscle weakness/pain, joint pain/swelling, eye pain/redness, vision problems, chest pain/pressure, persistent nausea/vomiting, unusual weakness/tiredness, dark urine, yellowing eyes/skin.

This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have any of the following symptoms because these products may make them worse. Tell your doctor right away if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.

Interactions

What drugs may interact with Rifabutin?

Some products that may interact with this drug include: azole antifungals (such as fluconazole, itraconazole, voriconazole), ciprofloxacin, delavirdine, macrolide antibiotics (such as clarithromycin).

Rifabutin can speed up the removal of other medications from your body, which may affect how they work. Examples of affected drugs include aprepitant/fosaprepitant, lurasidone, phenytoin, ranolazine, suvorexant, tacrolimus, tasimelteon, “blood thinners” (such as warfarin), calcium channel blockers (such as diltiazem, verapamil), certain combination products used to treat chronic hepatitis C (ombitasvir/paritaprevir/ritonavir), among others.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use additional reliable birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.

Rifabutin may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with Rifabutin?

Rifabutin may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Rifabutin?

Rifabutin may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this Rifabutin.

What is the dose of Rifabutin for an adult?

Usual Adult Dose for Mycobacterium avium-intracellulare – Prophylaxis

300 mg orally once a day. If nausea of vomiting becomes a problem, rifabutin 150 mg orally every 12 hours is an alternative regimen.

Usual Adult Dose for Mycobacterium avium-intracellulare – Treatment

300 mg orally once a day. If nausea or vomiting becomes a problem, rifabutin 150 mg orally every 12 hours is an alternative regimen. Therapy often consists of clarithromycin and 2-4 other drugs such as ethambutol, rifampin, clofazimine, and/or other agents. The duration of treatment is generally 18 to 24 months. In immunocompromised patients therapy often consists of clarithromycin or azithromycin and 1 to 3 other drugs such as ethambutol, clofazimine, ciprofloxacin, ofloxacin, rifampin, rifabutin, or amikacin. As long as a clinical and microbiological response is documented, therapy should be continued for life.

Usual Adult Dose for Tuberculosis – Prophylaxis

300 mg orally once a day. If nausea of vomiting becomes a problem, rifabutin 150 mg orally every 12 hours is an alternative regimen.

Rifabutin is recommended by the USPHS/IDSA (U.S. Public Health Service/Infectious Diseases Society of America) Prevention of Opportunistic Infections Working Group as an alternative to rifampin for chemoprophylaxis when exposure to isoniazid-resistant tuberculosis is suspected.

For HIV-infected patients, chemoprophylaxis is recommended for those with a positive tuberculin skin test (greater than or equal to 5 mm), prior positive skin test result without treatment, or contact with cases of active tuberculosis. In addition, tuberculin skin test negative, HIV-infected patients from high risk groups or geographic areas with a high prevalence of Mycobacterium tuberculosis may be candidates for chemoprophylaxis. Active tuberculosis should be ruled out prior to initiating preventive therapy.

There isn’t general agreement on how to use rifabutin for preventive therapy. The decision to use non-isoniazid-containing regimens for chemoprophylaxis should require consultation with public health authorities.

Rifabutin is typically administered for 6 months to prevent the development of active tuberculosis in patients with no complicating factors. Patients with complicating factors such as HIV infection, diabetes, hematologic malignancy, or scars on chest X-ray should receive prophylaxis for 12 months.

Usual Adult Dose for Tuberculosis – HIV Positive

300 mg orally once a day. If nausea of vomiting becomes a problem, rifabutin 150 mg orally every 12 hours is an alternative regimen.

Due to the serious public and personal health risk associated with TB, the American Thoracic Society and the Centers for Disease Control strongly recommend giving anti-TB drugs in a directly observed therapy (DOT) program. If daily self-administered therapy is used, many experts strongly recommend use of combination preparations to decrease the chance of medication noncompliance.

The duration of therapy depends on the susceptibility of the organism. Pulmonary TB should be treated for a minimum of 6 months. In HIV-positive individuals, some experts believe that therapy should be continued for at least 9 months or 6 months beyond culture conversion. This practice is controversial. The current ATS/CDC recommendations are to treat TB in patients with HIV no differently than in those who are HIV-negative. However, before administering rifampin, providers must take into consideration the important drug-drug interactions that exist between rifampin and the non-nucleoside reverse transcriptase inhibitor and protease inhibitor agents used to treat HIV infection. Rifabutin is a safer agent to use in HIV-infected individuals taking certain antiretroviral agents.

In general, six-month regimens are effective if pyrazinamide (PZA) and isoniazid (INH) are included in the first two months of therapy. Recommended regimens are as follows.

Rate of INH resistance known to be less than 4%: Daily rifampin (RIF) or rifabutin (RFB) + INH + PZA for 2 months, followed by daily RIF or RFB + INH therapy for 4 months. If susceptibility test confirms INH resistance then follow regimen for INH resistant TB.

Rate of INH resistance is greater than or equal to 4% or unknown (and the patient will be compliant): Daily RIF or RFB + INH + PZA + either streptomycin (SM) or ethambutol (ETB) until susceptibility data is available. If no INH resistance, then continue with daily RIF or RFB + INH + PZA for a total of 2 months and finish with RIF or RFB + INH daily to complete 6 months of therapy. If confirmed INH resistance, then follow regimen for INH resistant TB.

Rate of INH resistance is greater than or equal to 4% or unknown (and the patient is noncompliant or unreliable): DOT with daily RIF or RFB + INH + PZA + either SM or ETB for 2 weeks then 2 to 3 times a week for 6 weeks. Therapy should then be continued with RIF or RFB + INH 2 to 3 times a week to complete 6 months of therapy. An alternative DOT regimen is RIF or RFB + INH + PZA + either SM or ETB 3 times a week for 6 months. Once susceptibility data is available and INH resistance is confirmed then follow regimen for INH resistant TB.

Confirmed INH resistant TB: DOT with daily RIF or RFB + ETB + PZA for 18 months or until sputum is culture negative for at least 12 months. If possible, the treatment of drug-resistant TB should be discussed with an expert in the treatment of such patients.

Liver Dose Adjustments

Dose reduction may be necessary in patients with severe liver dysfunction.

Dose Adjustments

Dose adjustments may be necessary when administered with protease inhibitors or non-nucleoside reverse transcriptase inhibitor. The dose should be increased to 450 mg or 600 mg when given with efavirenz.

Precautions

Rifabutin prophylaxis must not be administered to patients with active tuberculosis. Among HIV positive patients, tuberculosis is common and may present with atypical or extrapulmonary findings. Patients are likely to have a nonreactive purified protein derivative (PPD) test despite active disease. In addition to chest x-ray and sputum culture, the following studies may be useful in the diagnosis of tuberculosis in the HIV positive patient: blood culture, urine culture, or biopsy of a suspicious lymph node.

The administration of rifabutin in the absence of appropriate antituberculous agents to patients with active tuberculosis (TB) may induce organisms resistant to rifabutin and other rifamycins, including rifampin and rifapentine. Therefore, active TB must be ruled out prior to institution of rifabutin therapy for Mycobacterium avium complex prophylaxis or other conditions where rifabutin might be used alone. Patients who develop symptoms consistent with active TB during rifabutin therapy should be evaluated promptly so that an effective antituberculosis regimen may be administered if necessary.

Clostridium difficile associated diarrhea (CDAD) has been observed with use of nearly all antibacterial agents, including rifabutin, and may range in severity from mild diarrhea to fatal colitis. Therapy with antibacterial agents alters the normal flora of the colon leading to overgrowth of Clostridium difficile. Clostridium difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of Clostridium difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial treatment and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or observed, ongoing antibiotic use not directed against Clostridium difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of Clostridium difficile, and surgical evaluation should be instituted as clinically indicated.

Rifabutin may cause an orange-brown discoloration of skin, urine, feces, saliva, sputum, tears, and sweat. Permanent discoloration of contact lens may occur.

Neutropenia and rarely thrombocytopenia has been associated with the use of rifabutin. Therefore, periodic hematologic tests should be performed during therapy with the rifabutin.

Clinical studies of rifabutin did not include sufficient numbers of patients aged 65 and over to determine whether they respond differently from younger patients. Other observed clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for elderly patients should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other therapy.

Dialysis

Rifabutin is not dialyzable.

What is the dose of Rifabutin for a child?

Usual Pediatric Dose for Mycobacterium avium-intracellulare – Treatment

5 mg/kg/day orally has been used in a limited number of cases. Used in combination with at least 2 other antimicrobials. Doses of rifabutin may be administered mixed with foods such as applesauce.

Precautions

Safety and effectiveness of rifabutin for prophylaxis of MAC in children have not been determined. Limited safety data are available from treatment use in 22 HIV-positive children with MAC who were administered rifabutin in combination with at least two other antimycobacterials for periods from 1 to 183 weeks. Adverse effects were similar to those observed in the adult population, and included leucopenia, neutropenia and rash. In addition, corneal deposits have been reported in some patients during routine ophthalmologic surveillance of HIV-positive pediatric patients receiving rifabutin as part of a multiple-drug regimen for MAC prophylaxis. These are tiny, almost transparent, asymptomatic peripheral and central corneal deposits that do not impair vision. Doses of rifabutin may be given mixed with food such as applesauce.

How is Rifabutin available?

Rifabutin is available in the following dosage forms and strengths:

  • Oral capsule.

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Rifabutin, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

 

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: April 21, 2018 | Last Modified: April 21, 2018

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