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'''Meningococcal Carriers'''
'''Meningococcal Carriers'''


Adults: For adults, it is recommended that 600 mg rifampin be administered twice daily for two days.
* Adults: For adults, it is recommended that 600 mg rifampin be administered twice daily for two days.


'''Preparation of Extemporaneous Oral Suspension'''
'''Preparation of Extemporaneous Oral Suspension'''


For pediatric and adult patients in whom capsule swallowing is difficult or where lower doses are needed, a liquid suspension may be prepared as follows:
* For patients in whom capsule swallowing is difficult or where lower doses are needed, a liquid suspension may be prepared as follows:


Rifampin 1% w/v suspension (10 mg/mL) can be compounded using Simple Syrup (Syrup NF):
:*Rifampin 1% w/v suspension (10 mg/mL) can be compounded using Simple Syrup (Syrup NF):


Empty the contents of four Rifampin 300 mg capsules or eight Rifampin 150 mg capsules onto a piece of weighing paper.
:*Empty the contents of four Rifampin 300 mg capsules or eight Rifampin 150 mg capsules onto a piece of weighing paper.
If necessary, gently crush the capsule contents with a spatula to produce a fine powder.
 
Transfer the rifampin powder blend to a 4-ounce amber glass or plastic (high density polyethylene [HDPE], polypropylene, or polycarbonate) prescription bottle.
:*If necessary, gently crush the capsule contents with a spatula to produce a fine powder.
Rinse the paper and spatula with 20 mL of syrup, and add the rinse to the bottle. Shake vigorously.
 
Add 100 mL of syrup to the bottle and shake vigorously.
:*Transfer the rifampin powder blend to a 4-ounce amber glass or plastic (high density polyethylene [HDPE], polypropylene, or polycarbonate) prescription bottle.
This compounding procedure results in a 1% w/v suspension containing 10 mg rifampin/mL. Stability studies indicate that the suspension is stable when stored at room temperature (25 ± 3°C) or in a refrigerator (2-8°C) for four weeks. This extemporaneously prepared suspension must be shaken well prior to administration
 
:*Rinse the paper and spatula with 20 mL of syrup, and add the rinse to the bottle. Shake vigorously.
 
:*Add 100 mL of syrup to the bottle and shake vigorously.
 
:*This compounding procedure results in a 1% w/v suspension containing 10 mg rifampin/mL. Stability studies indicate that the suspension is stable when stored at room temperature (25 ± 3°C) or in a refrigerator (2-8°C) for four weeks. This extemporaneously prepared suspension must be shaken well prior to administration
|offLabelAdultGuideSupport=There is limited information regarding <i>Guideline-Supported Off-Label Use</i> of Rifampin in adult patients.
|offLabelAdultGuideSupport=There is limited information regarding <i>Guideline-Supported Off-Label Use</i> of Rifampin in adult patients.
|offLabelAdultNoGuideSupport===Indications==
|offLabelAdultNoGuideSupport===Indications==
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* '''Leprosy'''
* '''Leprosy'''
''Dosing''
''Dosing''
:*Leprosy: 10 mg/kg/day ORALLY or IV once daily (max, 600 mg/day), in combination with dapsone, with or without clofazimine
:*Leprosy: 10 mg/kg/day orally or IV once daily (max, 600 mg/day), in combination with dapsone, with or without clofazimine
|contraindications=* Rifampin is contraindicated in patients with a history of hypersensitivity to rifampin or any of the components, or to any of the rifamycins.  
|contraindications=* Rifampin is contraindicated in patients with a history of hypersensitivity to rifampin or any of the components, or to any of the rifamycins.  


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|drugInteractions=* Healthy subjects who received rifampin 600 mg once daily concomitantly with saquinavir 1000 mg/ritonavir 100 mg twice daily (ritonavir-boosted saquinavir) developed severe hepatocellular toxicity. Therefore, concomitant use of these medications is contraindicated.  
|drugInteractions=* Healthy subjects who received rifampin 600 mg once daily concomitantly with saquinavir 1000 mg/ritonavir 100 mg twice daily (ritonavir-boosted saquinavir) developed severe hepatocellular toxicity. Therefore, concomitant use of these medications is contraindicated.  


'''Enzyme Induction''': Rifampin is known to induce certain cytochrome P-450 enzymes. Administration of rifampin with drugs that undergo biotransformation through these metabolic pathways may accelerate elimination of coadministered drugs. To maintain optimum therapeutic blood levels, dosages of drugs metabolized by these enzymes may require adjustment when starting or stopping concomitantly administered rifampin.
'''Enzyme Induction''':  


Rifampin has been reported to substantially decrease the plasma concentrations of the following antiviral drugs: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir. These antiviral drugs must not be co-administered with rifampin.  
* Rifampin is known to induce certain cytochrome P-450 enzymes. Administration of rifampin with drugs that undergo biotransformation through these metabolic pathways may accelerate elimination of coadministered drugs. To maintain optimum therapeutic blood levels, dosages of drugs metabolized by these enzymes may require adjustment when starting or stopping concomitantly administered rifampin.


Rifampin has been reported to accelerate the metabolism of the following drugs: anticonvulsants (e.g., phenytoin), digitoxin, antiarrhythmics (e.g., disopyramide, mexiletine, quinidine, tocainide), oral anticoagulants, antifungals (e.g., fluconazole, itraconazole, ketoconazole), barbiturates, beta-blockers, calcium channel blockers (e.g., diltiazem, nifedipine, verapamil), chloramphenicol, clarithromycin, corticosteroids, cyclosporine, cardiac glycoside preparations, clofibrate, oral or other systemic hormonal contraceptives, dapsone, diazepam, doxycycline, fluoroquinolones (e.g., ciprofloxacin), haloperidol, oral hypoglycemic agents (sulfonylureas), levothyroxine, methadone, narcotic analgesics, progestins, quinine, tacrolimus, theophylline, tricyclic antidepressants (e.g., amitriptyline, nortriptyline) and zidovudine. It may be necessary to adjust the dosages of these drugs if they are given concurrently with rifampin.
* Rifampin has been reported to substantially decrease the plasma concentrations of the following antiviral drugs: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir. These antiviral drugs must not be co-administered with rifampin.  


Patients using oral or other systemic hormonal contraceptives should be advised to change to non-hormonal methods of birth control during rifampin therapy.
* Rifampin has been reported to accelerate the metabolism of the following drugs: anticonvulsants (e.g., phenytoin), digitoxin, antiarrhythmics (e.g., disopyramide, mexiletine, quinidine, tocainide), oral anticoagulants, antifungals (e.g., fluconazole, itraconazole, ketoconazole), barbiturates, beta-blockers, calcium channel blockers (e.g., diltiazem, nifedipine, verapamil), chloramphenicol, clarithromycin, corticosteroids, cyclosporine, cardiac glycoside preparations, clofibrate, oral or other systemic hormonal contraceptives, dapsone, diazepam, doxycycline, fluoroquinolones (e.g., ciprofloxacin), haloperidol, oral hypoglycemic agents (sulfonylureas), levothyroxine, methadone, narcotic analgesics, progestins, quinine, tacrolimus, theophylline, tricyclic antidepressants (e.g., amitriptyline, nortriptyline) and zidovudine. It may be necessary to adjust the dosages of these drugs if they are given concurrently with rifampin.


Rifampin has been observed to increase the requirements for anticoagulant drugs of the coumarin type. In patients receiving anticoagulants and rifampin concurrently, it is recommended that the prothrombin time be performed daily or as frequently as necessary to establish and maintain the required dose of anticoagulant.
* Patients using oral or other systemic hormonal contraceptives should be advised to change to non-hormonal methods of birth control during rifampin therapy.


'''Other Interactions''': When the two drugs were taken concomitantly, decreased concentrations of atovaquone and increased concentrations of rifampin were observed.
* Rifampin has been observed to increase the requirements for anticoagulant drugs of the coumarin type. In patients receiving anticoagulants and rifampin concurrently, it is recommended that the prothrombin time be performed daily or as frequently as necessary to establish and maintain the required dose of anticoagulant.


Concurrent use of ketoconazole and rifampin has resulted in decreased serum concentrations of both drugs. Concurrent use of rifampin and enalapril has resulted in decreased concentrations of enalaprilat, the active metabolite of enalapril. Dosage adjustments should be made if indicated by the patient's clinical condition.
'''Other Interactions''':


Concomitant antacid administration may reduce the absorption of rifampin. Daily doses of rifampin should be given at least 1 hour before the ingestion of antacids.
* When the two drugs were taken concomitantly, decreased concentrations of atovaquone and increased concentrations of rifampin were observed.


Probenecid and cotrimoxazole have been reported to increase the blood level of rifampin.
* Concurrent use of ketoconazole and rifampin has resulted in decreased serum concentrations of both drugs. Concurrent use of rifampin and enalapril has resulted in decreased concentrations of enalaprilat, the active metabolite of enalapril. Dosage adjustments should be made if indicated by the patient's clinical condition.


When rifampin is given concomitantly with either halothane or isoniazid, the potential for hepatotoxicity is increased. The concomitant use of rifampin and halothane should be avoided. Patients receiving both rifampin and isoniazid should be monitored close for hepatotoxicity.
* Concomitant antacid administration may reduce the absorption of rifampin. Daily doses of rifampin should be given at least 1 hour before the ingestion of antacids.


Plasma concentrations of sulfapyridine may be reduced following the concomitant administration of sulfasalazine and rifampin. This finding may be the result of alteration in the colonic bacteria responsible for the reduction of sulfasalazine to sulfapyridine and mesalamine.
* Probenecid and cotrimoxazole have been reported to increase the blood level of rifampin.
 
* When rifampin is given concomitantly with either halothane or isoniazid, the potential for hepatotoxicity is increased. The concomitant use of rifampin and halothane should be avoided. Patients receiving both rifampin and isoniazid should be monitored close for hepatotoxicity.
 
* Plasma concentrations of sulfapyridine may be reduced following the concomitant administration of sulfasalazine and rifampin. This finding may be the result of alteration in the colonic bacteria responsible for the reduction of sulfasalazine to sulfapyridine and mesalamine.
|useInPregnancyFDA='''Pregnancy-Teratogenic Effects'''
|useInPregnancyFDA='''Pregnancy-Teratogenic Effects'''


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|drugBox=[[File:Rifampin structure02.png|thumb|none|600px|This image is provided by the National Library of Medicine.]]
|drugBox=[[File:Rifampin structure02.png|thumb|none|600px|This image is provided by the National Library of Medicine.]]
|mechAction=Rifampin inhibits DNA-dependent RNA polymerase activity in susceptible Mycobacterium tuberculosis organisms. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme.
|mechAction=Rifampin inhibits DNA-dependent RNA polymerase activity in susceptible Mycobacterium tuberculosis organisms. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme.
|structure=Rifampin capsules, USP for oral administration contain 150 mg or 300 mg rifampin per capsule. The 150 mg and 300 mg capsules also contain, as inactive ingredients: colloidal silicon dioxide, corn starch, FD&C Blue No. 1, FD&C Red No. 40, gelatin, lactose monohydrate, magnesium stearate, sodium lauryl sulfate, talc, and titanium dioxide.
|structure=* Rifampin capsules, USP for oral administration contain 150 mg or 300 mg rifampin per capsule. The 150 mg and 300 mg capsules also contain, as inactive ingredients: colloidal silicon dioxide, corn starch, FD&C Blue No. 1, FD&C Red No. 40, gelatin, lactose monohydrate, magnesium stearate, sodium lauryl sulfate, talc, and titanium dioxide.


The printing ink contains ammonium hydroxide, isopropyl alcohol, n-butyl alcohol, pharmaceutical glaze, propylene glycol, simethicone, and titanium dioxide
* The printing ink contains ammonium hydroxide, isopropyl alcohol, n-butyl alcohol, pharmaceutical glaze, propylene glycol, simethicone, and titanium dioxide


Rifampin is a semisynthetic antibiotic derivative of rifamycin SV. Rifampin is a red-brown crystalline powder very slightly soluble in water at neutral pH, freely soluble in chloroform, soluble in ethyl acetate and in methanol. Its molecular weight is 822.95 and its chemical formula is C43H58N4O12.
* Rifampin is a semisynthetic antibiotic derivative of rifamycin SV. Rifampin is a red-brown crystalline powder very slightly soluble in water at neutral pH, freely soluble in chloroform, soluble in ethyl acetate and in methanol. Its molecular weight is 822.95 and its chemical formula is C43H58N4O12.


The chemical name for rifampin is either:
* The chemical name for rifampin is either:


3-[[(4-Methyl-1-piperazinyl)imino]]methyl]rifamycin
3-[[(4-Methyl-1-piperazinyl)imino]]methyl]rifamycin
Line 231: Line 240:
5,6,9,17,19,21-hexahydroxy-23-methoxy-2,4,12,16,20,22-heptamethyl-8-[N-(4-methyl-1-piperazinyl)formimidoyl]-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-1,11(2H)-dione 21-acetate.
5,6,9,17,19,21-hexahydroxy-23-methoxy-2,4,12,16,20,22-heptamethyl-8-[N-(4-methyl-1-piperazinyl)formimidoyl]-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-1,11(2H)-dione 21-acetate.


Its structural formula is:
* Its structural formula is:
 
[[File:Rifampin structure01.png|thumb|none|600px|This image is provided by the National Library of Medicine.]]
 
 
[[File:Rifampin structure01.png|thumb|none|400px|This image is provided by the National Library of Medicine.]]
|PD=There is limited information regarding <i>Pharmacodynamics</i> of {{PAGENAME}} in the drug label.
|PD=There is limited information regarding <i>Pharmacodynamics</i> of {{PAGENAME}} in the drug label.
|PK=There is limited information regarding <i>Pharmacokinetics</i> of {{PAGENAME}} in the drug label.
|PK=There is limited information regarding <i>Pharmacokinetics</i> of {{PAGENAME}} in the drug label.
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* Rimactane
* Rimactane
|drugShortage=
|drugShortage=
}}
{{PillImage
|fileName=No image.jpg
}}
}}
{{LabelImage
{{LabelImage
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|fileName=Rifampin fig.jpg
|fileName=Rifampin fig.jpg
}}
}}
<!--Pill Image-->


<!--Label Display Image-->




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<!--Category-->
<!--Category-->


[[Category:Rifamycin antibiotics]]
[[Category:Drug]]
[[Category:Drug]]

Latest revision as of 17:04, 20 August 2015

Rifampin (oral)
Adult Indications & Dosage
Pediatric Indications & Dosage
Contraindications
Warnings & Precautions
Adverse Reactions
Drug Interactions
Use in Specific Populations
Administration & Monitoring
Overdosage
Pharmacology
Clinical Studies
How Supplied
Images
Patient Counseling Information
Precautions with Alcohol
Brand Names
Look-Alike Names

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Kiran Singh, M.D. [2]

Disclaimer

WikiDoc MAKES NO GUARANTEE OF VALIDITY. WikiDoc is not a professional health care provider, nor is it a suitable replacement for a licensed healthcare provider. WikiDoc is intended to be an educational tool, not a tool for any form of healthcare delivery. The educational content on WikiDoc drug pages is based upon the FDA package insert, National Library of Medicine content and practice guidelines / consensus statements. WikiDoc does not promote the administration of any medication or device that is not consistent with its labeling. Please read our full disclaimer here.

Overview

Rifampin (oral) is an antitubercular drug that is FDA approved for the treatment of tuberculosis, meningococcal carrier state,. Common adverse reactions include heartburn, epigastric distress, anorexia, nausea, vomiting, jaundice, flatulence, cramps.

Adult Indications and Dosage

FDA-Labeled Indications and Dosage (Adult)

Indications

  • In the treatment of both tuberculosis and the meningococcal carrier state, the small number of resistant cells present within large populations of susceptible cells can rapidly become the predominant type. Bacteriologic cultures should be obtained before the start of therapy to confirm the susceptibility of the organism to rifampin and they should be repeated throughout therapy to monitor the response to treatment. Since resistance can emerge rapidly, susceptibility tests should be performed in the event of persistent positive cultures during the course of treatment. If test results show resistance to rifampin and the patient is not responding to therapy, the drug regimen should be modified.

Tuberculosis

  • Rifampin is indicated in the treatment of all forms of tuberculosis.
  • A three-drug regimen consisting of rifampin, isoniazid, and pyrazinamide [e.g., RIFATER®]5 is recommended in the initial phase of short-course therapy which is usually continued for 2 months. The Advisory Council for the Elimination of Tuberculosis, the American Thoracic Society, and Centers for Disease Control and Prevention recommend that either streptomycin or ethambutol be added as a fourth drug in a regimen containing isoniazid (INH), rifampin, and pyrazinamide for initial treatment of tuberculosis unless the likelihood of INH resistance is very low. The need for a fourth drug should be reassessed when the results of susceptibility testing are known. If community rates of INH resistance are currently less than 4%, an initial treatment regimen with less than four drugs may be considered.
  • Following the initial phase, treatment should be continued with rifampin and isoniazid [e.g., RIFAMATE®]6 for at least 4 months. Treatment should be continued for longer if the patient is still sputum or culture positive, if resistant organisms are present, or if the patient is HIV positive.

Meningococcal Carriers

  • Rifampin is indicated for the treatment of asymptomatic carriers of Neisseria meningitidis to eliminate meningococci from the nasopharynx. Rifampin is not indicated for the treatment of meningococcal infection because of the possibility of the rapid emergence of resistant organisms.
  • Rifampin should not be used indiscriminately, and therefore, diagnostic laboratory procedures, including serotyping and susceptibility testing, should be performed for establishment of the carrier state and the correct treatment. So that the usefulness of rifampin in the treatment of asymptomatic meningococcal carriers is preserved, the drug should be used only when the risk of meningococcal disease is high.
  • To reduce the development of drug-resistant bacteria and maintain the effectiveness of rifampin and other antibacterial drugs, rifampin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy

Dosing

Tuberculosis

  • Adults: 10 mg/kg, in a single daily administration, not to exceed 600 mg/day.
  • It is recommended that oral rifampin be administered once daily, either 1 hour before or 2 hours after a meal with a full glass of water.
  • Rifampin is indicated in the treatment of all forms of tuberculosis. A three-drug regimen consisting of rifampin, isoniazid, and pyrazinamide [e.g., RIFATER®]5 is recommended in the initial phase of short-course therapy which is usually continued for 2 months. The Advisory Council for the Elimination of Tuberculosis, the American Thoracic Society, and the Centers for Disease Control and Prevention recommend that either streptomycin or ethambutol be added as a fourth drug in a regimen containing isoniazid (INH), rifampin and pyrazinamide for initial treatment of tuberculosis unless the likelihood of INH resistance is very low. The need for a fourth drug should be reassessed when the results of susceptibility testing are known. If community rates of INH resistance are currently less than 4%, an initial treatment regimen with less than four drugs may be considered.
  • Following the initial phase, treatment should be continued with rifampin and isoniazid [RIFAMATE®]6. for at least 4 months. Treatment should be continued for longer if the patient is still sputum or culture positive, if resistant organisms are present, or if the patient is HIV positive.

Meningococcal Carriers

  • Adults: For adults, it is recommended that 600 mg rifampin be administered twice daily for two days.

Preparation of Extemporaneous Oral Suspension

  • For patients in whom capsule swallowing is difficult or where lower doses are needed, a liquid suspension may be prepared as follows:
  • Rifampin 1% w/v suspension (10 mg/mL) can be compounded using Simple Syrup (Syrup NF):
  • Empty the contents of four Rifampin 300 mg capsules or eight Rifampin 150 mg capsules onto a piece of weighing paper.
  • If necessary, gently crush the capsule contents with a spatula to produce a fine powder.
  • Transfer the rifampin powder blend to a 4-ounce amber glass or plastic (high density polyethylene [HDPE], polypropylene, or polycarbonate) prescription bottle.
  • Rinse the paper and spatula with 20 mL of syrup, and add the rinse to the bottle. Shake vigorously.
  • Add 100 mL of syrup to the bottle and shake vigorously.
  • This compounding procedure results in a 1% w/v suspension containing 10 mg rifampin/mL. Stability studies indicate that the suspension is stable when stored at room temperature (25 ± 3°C) or in a refrigerator (2-8°C) for four weeks. This extemporaneously prepared suspension must be shaken well prior to administration

Off-Label Use and Dosage (Adult)

Guideline-Supported Use

There is limited information regarding Guideline-Supported Off-Label Use of Rifampin in adult patients.

Non–Guideline-Supported Use

Indications

  • Atypical mycobacterial infection
  • Haemophilus influenzae infection; Prophylaxis
  • Leprosy

Dosing:Leprosy: 600 mg orally or IV once daily, in combination with dapsone, with or without clofazimine

  • Mycobacterium avium complex infection, lung disease

Dosing

  • Mycobacterium avium complex infection, Lung disease: (nodular/bronchiectatic disease) initial, 600 mg orally 3 times weekly in combination with clarithromycin 1000 mg or azithromycin 500 to 600 mg orally 3 times weekly plus ethambutol 25 mg/kg orally 3 times weekly[1]
  • Mycobacterium avium complex infection, Lung disease: (cavitary disease) initial, 10 mg/kg orally daily (max, 600 mg daily) in combination with clarithromycin 1000 mg orally daily (or 500 mg twice daily) OR azithromycin 250 mg orally daily plus ethambutol 15 mg/kg orally daily; consider addition of streptomycin OR amikacin[1]
  • Mycobacterium avium complex infection, Lung disease: (severe or previously treated disease) rifampin 10 mg/kg orally daily (max, 600 mg) OR rifabutin 150 to 300 mg orally daily in combination with clarithromycin 1000 mg orally daily (or 500 mg twice daily) OR azithromycin 250 mg orally daily plus ethambutol 15 mg/kg orally daily plus streptomycin OR amikacin[1]

Pediatric Indications and Dosage

FDA-Labeled Indications and Dosage (Pediatric)

There is limited information regarding FDA-Labeled Use of Rifampin (oral) in pediatric patients.

Off-Label Use and Dosage (Pediatric)

Guideline-Supported Use

There is limited information regarding Off-Label Guideline-Supported Use of Rifampin in pediatric patients.

Non–Guideline-Supported Use

Indications

  • Haemophilus influenzae infection; Prophylaxis
  • Leprosy

Dosing

  • Leprosy: 10 mg/kg/day orally or IV once daily (max, 600 mg/day), in combination with dapsone, with or without clofazimine

Contraindications

  • Rifampin is contraindicated in patients with a history of hypersensitivity to rifampin or any of the components, or to any of the rifamycins.
  • Rifampin is contraindicated in patients who are also receiving ritonavir-boosted saquinavir due to an increased risk of severe hepatocellular toxicity.
  • Rifampin is contraindicated in patients who are also receiving atazanavir, darunavir, fosamprenavir, saquinavir, or tipranavir due to the potential of rifampin to substantially decrease plasma concentrations of these antiviral drugs, which may result in loss of antiviral efficacy and/or development of viral resistance.

Warnings

  • Rifampin has been shown to produce liver dysfunction. Fatalities associated with jaundice have occurred in patients with liver disease and in patients taking rifampin with other hepatotoxic agents. Patients with impaired liver function should be given rifampin only in cases of necessity and then with caution and under strict medical supervision. In these patients, careful monitoring of liver function, especially SGPT/ALT and SGOT/AST should be carried out prior to therapy and then every 2 to 4 weeks during therapy. If signs of hepatocellular damage occur, rifampin should be withdrawn.
  • In some cases, hyperbilirubinemia resulting from competition between rifampin and bilirubin for excretory pathways of the liver at the cell level can occur in the early days of treatment. An isolated report showing a moderate rise in bilirubin and/or transaminase level is not in itself an indication for interrupting treatment; rather, the decision should be made after repeating the tests, noting trends in the levels, and considering them in conjunction with the patient's clinical condition.
  • Rifampin has enzyme-inducing properties, including induction of delta amino levulinic acid synthetase. Isolated reports have associated porphyria exacerbation with rifampin administration.
  • The possibility of rapid emergence of resistant meningococci restricts the use of rifampin to short-term treatment of the asymptomatic carrier state.

Rifampin is not to be used for the treatment of meningococcal disease

Adverse Reactions

Clinical Trials Experience

Gastrointestinal

Hepatic

  • Transient abnormalities in liver function tests (e.g., elevations in serum bilirubin, alkaline phosphatase, serum transaminases) have been observed. Rarely, hepatitis or a shock-like syndrome with hepatic involvement and abnormal liver function tests has been reported.

Hematologic

  • Thrombocytopenia has occurred primarily with high dose intermittent therapy, but has also been noted after resumption of interrupted treatment. It rarely occurs during well supervised daily therapy. This effect is reversible if the drug is discontinued as soon as purpura occurs. Cerebral hemorrhage and fatalities have been reported when rifampin administration has been continued or resumed after the appearance of purpura.

Central Nervous System

  • Rare reports of myopathy have also been observed.

Ocular

  • Visual disturbances have been observed.

Endocrine

  • Menstrual disturbances have been observed.

Renal

  • Elevations in BUN and serum uric acid have been reported. Rarely, hemolysis, hemoglobinuria, hematuria, interstitial nephritis, acute tubular necrosis, renal insufficiency, and acute renal failure have been noted. These are generally considered to be hypersensitivity reactions. They usually occur during intermittent therapy or when treatment is resumed following intentional or accidental interruption of a daily dosage regimen, and are reversible when rifampin is discontinued and appropriate therapy instituted.

Dermatologic

  • Cutaneous reactions are mild and self-limiting and do not appear to be hypersensitivity reactions. Typically, they consist of flushing and itching with or without a rash. More serious cutaneous reactions which may be due to hypersensitivity occur but are uncommon.

Hypersensitivity Reactions

Miscellaneous

Postmarketing Experience

There is limited information regarding Postmarketing Experience of Rifampin in the drug label.

Drug Interactions

  • Healthy subjects who received rifampin 600 mg once daily concomitantly with saquinavir 1000 mg/ritonavir 100 mg twice daily (ritonavir-boosted saquinavir) developed severe hepatocellular toxicity. Therefore, concomitant use of these medications is contraindicated.

Enzyme Induction:

  • Rifampin is known to induce certain cytochrome P-450 enzymes. Administration of rifampin with drugs that undergo biotransformation through these metabolic pathways may accelerate elimination of coadministered drugs. To maintain optimum therapeutic blood levels, dosages of drugs metabolized by these enzymes may require adjustment when starting or stopping concomitantly administered rifampin.
  • Rifampin has been reported to substantially decrease the plasma concentrations of the following antiviral drugs: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir. These antiviral drugs must not be co-administered with rifampin.
  • Rifampin has been reported to accelerate the metabolism of the following drugs: anticonvulsants (e.g., phenytoin), digitoxin, antiarrhythmics (e.g., disopyramide, mexiletine, quinidine, tocainide), oral anticoagulants, antifungals (e.g., fluconazole, itraconazole, ketoconazole), barbiturates, beta-blockers, calcium channel blockers (e.g., diltiazem, nifedipine, verapamil), chloramphenicol, clarithromycin, corticosteroids, cyclosporine, cardiac glycoside preparations, clofibrate, oral or other systemic hormonal contraceptives, dapsone, diazepam, doxycycline, fluoroquinolones (e.g., ciprofloxacin), haloperidol, oral hypoglycemic agents (sulfonylureas), levothyroxine, methadone, narcotic analgesics, progestins, quinine, tacrolimus, theophylline, tricyclic antidepressants (e.g., amitriptyline, nortriptyline) and zidovudine. It may be necessary to adjust the dosages of these drugs if they are given concurrently with rifampin.
  • Patients using oral or other systemic hormonal contraceptives should be advised to change to non-hormonal methods of birth control during rifampin therapy.
  • Rifampin has been observed to increase the requirements for anticoagulant drugs of the coumarin type. In patients receiving anticoagulants and rifampin concurrently, it is recommended that the prothrombin time be performed daily or as frequently as necessary to establish and maintain the required dose of anticoagulant.

Other Interactions:

  • When the two drugs were taken concomitantly, decreased concentrations of atovaquone and increased concentrations of rifampin were observed.
  • Concurrent use of ketoconazole and rifampin has resulted in decreased serum concentrations of both drugs. Concurrent use of rifampin and enalapril has resulted in decreased concentrations of enalaprilat, the active metabolite of enalapril. Dosage adjustments should be made if indicated by the patient's clinical condition.
  • Concomitant antacid administration may reduce the absorption of rifampin. Daily doses of rifampin should be given at least 1 hour before the ingestion of antacids.
  • Probenecid and cotrimoxazole have been reported to increase the blood level of rifampin.
  • When rifampin is given concomitantly with either halothane or isoniazid, the potential for hepatotoxicity is increased. The concomitant use of rifampin and halothane should be avoided. Patients receiving both rifampin and isoniazid should be monitored close for hepatotoxicity.
  • Plasma concentrations of sulfapyridine may be reduced following the concomitant administration of sulfasalazine and rifampin. This finding may be the result of alteration in the colonic bacteria responsible for the reduction of sulfasalazine to sulfapyridine and mesalamine.

Use in Specific Populations

Pregnancy

Pregnancy Category (FDA): Pregnancy-Teratogenic Effects

Category C. Rifampin has been shown to be teratogenic in rodents. Congenital malformations, primarily spina bifida were increased in the offspring of pregnant rats given rifampin during organogenesis at oral doses of 150 to 250 mg/kg/day (about 1 to 2 times the maximum recommended human dose based on body surface area comparisons). Cleft palate was increased in a dose-dependent fashion in fetuses of pregnant mice treated at oral doses of 50 to 200 mg/kg (about 0.2 to 0.8 times the maximum recommended human dose based on body surface area comparisons). Imperfect osteogenesis and embryotoxicity were also reported in pregnant rabbits given rifampin at oral doses up to 200 mg/kg/day (about 3 times the maximum recommended human dose based on body surface area comparisons). There are no adequate and well-controlled studies of rifampin in pregnant women. Rifampin has been reported to cross the placental barrier and appear in cord blood. Rifampin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Pregnancy-Non-Teratogenic Effects

When administered during the last few weeks of pregnancy, rifampin can cause post-natal hemorrhages in the mother and infant for which treatment with vitamin K may be indicated.
Pregnancy Category (AUS):

  • Australian Drug Evaluation Committee (ADEC) Pregnancy Category

There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of Rifampin in women who are pregnant.

Labor and Delivery

There is no FDA guidance on use of Rifampin during labor and delivery.

Nursing Mothers

  • Because of the potential for tumorigenicity shown for rifampin in animal studies, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

There is no FDA guidance on the use of Rifampin with respect to pediatric patients.

Geriatic Use

Clinical studies of rifampin did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. Caution should therefore be observed in using rifampin in elderly patients.

Gender

There is no FDA guidance on the use of Rifampin with respect to specific gender populations.

Race

There is no FDA guidance on the use of Rifampin (oral) with respect to specific racial populations.

Renal Impairment

There is no FDA guidance on the use of Rifampin in patients with renal impairment.

Hepatic Impairment

There is no FDA guidance on the use of Rifampin in patients with hepatic impairment.

Females of Reproductive Potential and Males

There is no FDA guidance on the use of Rifampin in women of reproductive potentials and males.

Immunocompromised Patients

There is no FDA guidance one the use of Rifampin in patients who are immunocompromised.

Administration and Monitoring

Administration

  • Oral

Monitoring

There is limited information regarding Monitoring of Rifampin in the drug label.

IV Compatibility

There is limited information regarding IV Compatibility of Rifampin in the drug label.

Overdosage

Signs and Symptoms

  • Nausea, vomiting, abdominal pain, pruritus, headache, and increasing lethargy will probably occur within a short time after ingestion; unconsciousness may occur when there is severe hepatic disease. Transient increases in liver enzymes and/or bilirubin may occur. Brownish-red or orange discoloration of the skin, urine, sweat, saliva, tears, and feces will occur, and its intensity is proportional to the amount ingested.
  • Liver enlargement, possibly with tenderness, can develop within a few hours after severe overdosage; bilirubin levels may increase and jaundice may develop rapidly. Hepatic involvement may be more marked in patients with prior impairment of hepatic function. Other physical findings remain essentially normal. A direct effect upon the hematopoietic system, electrolyte levels, or acid-base balance is unlikely.

Acute Toxicity

The minimum acute lethal or toxic dose is not well established. However, nonfatal acute overdoses in adults have been reported with doses ranging from 9 to 12 gm rifampin. Fatal acute overdoses in adults have been reported with doses ranging from 14 to 60 gm. Alcohol or a history of alcohol abuse was involved in some of the fatal and nonfatal reports. Nonfatal overdoses in pediatric patients ages 1 to 4 years old of 100 mg/kg for one to two doses has been reported.

Treatment

Intensive support measures should be instituted and individual symptoms treated as they arise. The airway should be secured and adequate respiratory exchange established. Since nausea and vomiting are likely to be present, gastric lavage within the first 2 to 3 hours after ingestion is probably preferable to induction of emesis. Following evacuation of the gastric contents, the instillation of activated charcoal slurry into the stomach may help absorb any remaining drug from the gastrointestinal tract. Antiemetic medication may be required to control severe nausea and vomiting.

Active diuresis (with measured intake and output) will help promote excretion of the drug.

For severe cases, extracorporeal hemodialysis may be required. If this is not available, peritoneal dialysis can be used along with forced diuresis.

Pharmacology

This image is provided by the National Library of Medicine.

Mechanism of Action

Rifampin inhibits DNA-dependent RNA polymerase activity in susceptible Mycobacterium tuberculosis organisms. Specifically, it interacts with bacterial RNA polymerase but does not inhibit the mammalian enzyme.

Structure

  • Rifampin capsules, USP for oral administration contain 150 mg or 300 mg rifampin per capsule. The 150 mg and 300 mg capsules also contain, as inactive ingredients: colloidal silicon dioxide, corn starch, FD&C Blue No. 1, FD&C Red No. 40, gelatin, lactose monohydrate, magnesium stearate, sodium lauryl sulfate, talc, and titanium dioxide.
  • The printing ink contains ammonium hydroxide, isopropyl alcohol, n-butyl alcohol, pharmaceutical glaze, propylene glycol, simethicone, and titanium dioxide
  • Rifampin is a semisynthetic antibiotic derivative of rifamycin SV. Rifampin is a red-brown crystalline powder very slightly soluble in water at neutral pH, freely soluble in chloroform, soluble in ethyl acetate and in methanol. Its molecular weight is 822.95 and its chemical formula is C43H58N4O12.
  • The chemical name for rifampin is either:

3-(4-Methyl-1-piperazinyl)iminomethyl]rifamycin

or 5,6,9,17,19,21-hexahydroxy-23-methoxy-2,4,12,16,20,22-heptamethyl-8-[N-(4-methyl-1-piperazinyl)formimidoyl]-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-1,11(2H)-dione 21-acetate.

  • Its structural formula is:
This image is provided by the National Library of Medicine.

Pharmacodynamics

There is limited information regarding Pharmacodynamics of Rifampin (oral) in the drug label.

Pharmacokinetics

There is limited information regarding Pharmacokinetics of Rifampin (oral) in the drug label.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

  • A few cases of accelerated growth of lung carcinoma have been reported in man, but a causal relationship with the drug has not been established. Hepatomas were increased in female (C3Hf/DP) mice dosed for 60 weeks with rifampicin followed by an observation period of 46 weeks, at 20 to 120 mg/kg (equivalent to 0.1 to 0.5 times the maximum dosage used clinically, based on body surface area comparisons). There was no evidence of tumorigenicity in male C3Hf/DP mice or in similar studies in BALB/c mice, or in two year studies in Wistar rats.
  • There was no evidence of mutagenicity in both prokaryotic (Salmonella typhi, Escherichia coli) and eukaryotic (Saccharomyces cerevisiae) bacteria, Drosophila melanogaster, or ICR/Ha Swiss mice. An increase in chromatid breaks was noted when whole blood cell cultures were treated with rifampin. Increased frequency of chromosomal aberrations was observed in vitro in lymphocytes obtained from patients treated with combinations of rifampin, isoniazid, and pyrazinamide and combinations of streptomycin, rifampin, isoniazid, and pyrazinamide.

Clinical Studies

There is limited information regarding Clinical Studies of Rifampin (oral) in the drug label.

How Supplied

  • Rifampin Capsules, USP, 150 mg opaque orange capsules printed in white on one half of the capsule in radial print “Rifampin 150” and on the other half in radial print “VP/015”
  • Bottles of 30 (NDC 61748-015-30)
  • Unit Dose Boxes of 100 (NDC 61748-015-11)
  • Rifampin Capsules, USP, 300 mg opaque orange capsules printed in white on one half of the capsule in radial print “Rifampin 300” and on the other half in radial print “VP/018”
  • Bottles of 30 (NDC 61748-018-30)
  • Bottles of 60 (NDC 61748-018-60)
  • Bottles of 100 (NDC 61748-018-01)
  • Unit Dose Boxes of 100 (NDC 61748-018-11)

Storage

  • Storage: Store at 20-25°C (68-77°F) [See USP Controlled Room Temperature]. Store in a dry place. Avoid excessive heat. Protect from light. Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure

Images

Drug Images

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Package and Label Display Panel

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Patient Counseling Information

Information for Patients

Patients should be counseled that antibacterial drugs including rifampin should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When rifampin is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by rifampin or other antibacterial drugs in the future.

'The patient should be told that rifampin may produce a reddish coloration of the urine, sweat, sputum, and tears, and the patient should be forewarned of this'. Soft contact lenses may be permanently stained.

The patient should be advised that the reliability of oral or other systemic hormonal contraceptives may be affected; consideration should be given to using alternative contraceptive measures.

Patients should be instructed to take rifampin either 1 hour before or 2 hours after a meal with a full glass of water.

Patients should be instructed to notify their physicians promptly if they experience any of the following: fever, loss of appetite, malaise, nausea and vomiting, darkened urine, yellowish discoloration of the skin and eyes, and pain or swelling of the joints.

Compliance with the full course of therapy must be emphasized, and the importance of not missing any doses must be stressed.

Precautions with Alcohol

  • Alcohol-Rifampin (oral) interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.

Brand Names

  • Rifadin
  • Rimactane

Look-Alike Drug Names

There is limited information regarding Rifampin (oral) Look-Alike Drug Names in the drug label.

Drug Shortage Status

Price

References

The contents of this FDA label are provided by the National Library of Medicine.

  1. 1.0 1.1 1.2 Griffith DE, Aksamit T, Brown-Elliott BA, Catanzaro A, Daley C, Gordin F; et al. (2007). "An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases". Am J Respir Crit Care Med. 175 (4): 367–416. doi:10.1164/rccm.200604-571ST. PMID 17277290.

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