Drug Action
Rifaximin is a rifamycin that is poorly absorbed from the gastro-intestinal tract, and, therefore, should not be used to treat systemic infections.
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Drug reference
Rifaximin is a rifamycin that is poorly absorbed from the gastro-intestinal tract, and, therefore, should not be used to treat systemic infections.
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Travellers’ diarrhoea that is not associated with fever, bloody diarrhoea, blood or leucocytes in the stool, or 8 or more unformed stools in the previous 24 hours ▶BY MOUTH ▶Adult: 200 mg every 8 hours for 3 days Reduction in recurrence of hepatic encephalopathy ▶BY MOUTH ▶Adult: 550 mg twice daily
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Intestinal obstruction
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Contra-indicated if history of rifamycin hypersensitivity.
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Not recommended for diarrhoea associated with invasive organisms such as Campylobacter and Shigella.
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NICE decisions ▶Rifaximin for preventing episodes of overt hepatic encephalopathy (March 2015) NICE TA337 Rifaximin (Targaxan ®) is recommended, within its marketing authorisation, as an option for reducing the recurrence of episodes of overt hepatic encephalopathy in adults. www.nice.org.uk/guidance/ta337
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→Appendix 1: rifaximin
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▶Common or very common Arthralgia. ascites. constipation . depression. dizziness. dyspnoea. gastrointestinal discomfort. gastrointestinal disorders. headaches. muscle complaints. nausea. oedema. skin reactions. vomiting ▶Uncommon Anaemia. anxiety. appetite decreased. asthenia. balance impaired. concentration impaired. confusion. cough. diplopia. drowsiness. dry lips. dry mouth. dry throat. ear pain. fall. haematuria. hot flush. hyperhidrosis. hyperkalaemia. increased risk of infection. lymphocytosis. memory loss. muscle weakness. nasal complaints. neutropenia. oropharyngeal pain. pain. palpitations. polymenorrhoea. respiratory disorders. seizure. sensation abnormal. sleep disorders. sunburn. taste altered. urinary disorders. urine abnormalities. vertigo ▶Rare or very rare Hypertension. hypotension ▶Frequency not known Angioedema. syncope. thrombocytopenia. urine discolouration
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Manufacturer advises avoid—toxicity in animal studies.
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Unlikely to be present in milk in significant amounts, but manufacturer advises avoid. Infection
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▶When used for hepatic encephalopathy Manufacturer advises caution in severe impairment (risk of increased exposure).
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There can be variation in the licensing of different medicines containing the same drug. Forms available from special-order manufacturers include: oral suspension Tablet CAUTIONARY AND ADVISORY LABELS 9 (Xifaxanta ® brand only), 14 ▶Targaxan (Norgine Pharmaceuticals Ltd) Rifaximin 550 mg Targaxan 550mg tablets | 56 tablet P £259.23 DT = £259.23 ▶Xifaxanta (Norgine Pharmaceuticals Ltd) Rifaximin 200 mg Xifaxanta 200mg tablets | 9 tablet P £15.15 DT = £15.15 2.1 Anthrax Anthrax Treatment and post-exposure prophylaxis Inhalation or gastro-intestinal anthrax should be treated initially with either ciprofloxacin p. 590 or, in patients over 12 years, doxycycline p. 597 [unlicensed indication] combined with one or two other antibacterials (such as amoxicillin p. 579, benzylpenicillin sodium p. 577, chloramphenicol p. 601, clarithromycin p. 567, clindamycin p. 564, imipenem with cilastatin p. 548, rifampicin p. 615 [unlicensed indication], and vancomycin p. 562). When the condition improves and the sensitivity of the Bacillus anthracis strain is known, treatment may be switched to a single antibacterial. Treatment should continue for 60 days because germination may be delayed. Cutaneous anthrax should be treated with either ciprofloxacin [unlicensed indication] or doxycycline [unlicensed indication] for 7 days. Treatment may be switched to amoxicillin if the infecting strain is susceptible. Treatment may need to be extended to 60 days if exposure is due to aerosol. A combination of antibacterials for 14 days is recommended for cutaneous anthrax with systemic features, extensive oedema, or lesions of the head or neck. Ciprofloxacin or doxycycline may be given for post- exposure prophylaxis. If exposure is confirmed, antibacterial prophylaxis should continue for 60 days. Antibacterial prophylaxis may be switched to amoxicillin after 10–14 days if the strain of B. anthracis is susceptible. Vaccination against anthrax may allow the duration of antibacterial prophylaxis to be shortened. 2.2 Leprosy Leprosy Management Advice from a member of the Panel of Leprosy Opinion is Infection essential for the treatment of leprosy (Hansen’s disease). Details can be obtained from the Hospital for Tropical Diseases, London (telephone (020) 3456 7890). The World Health Organization has made recommendations to overcome the problem of dapsone below resistance and to prevent the emergence of resistance to other antileprotic drugs. Drugs recommended are dapsone, rifampicin p. 615, and clofazimine below. Other drugs with significant activity against Mycobacterium leprae include ofloxacin p. 593, minocycline p. 599 and clarithromycin p. 567, but none of these are as active as rifampicin; at present they should be reserved as second-line drugs for leprosy. A three-drug regimen is recommended for multibacillary leprosy (lepromatous, borderline-lepromatous, and borderline leprosy) and a two-drug regimen for paucibacillary leprosy (borderline-tuberculoid, tuberculoid, and indeterminate). Multibacillary leprosy should be treated with a combination of rifampicin, dapsone and clofazimine for at least 2 years. Treatment should be continued unchanged during both type I (reversal) or type II (erythema nodosum leprosum) reactions. During reversal reactions neuritic pain or weakness can herald the rapid onset of permanent nerve damage. Treatment with prednisolone p. 716 should be instituted at once. Mild type II reactions may respond to aspirin. Severe type II reactions may require corticosteroids; thalidomide p. 1014 [unlicensed] is also useful in patients who have become corticosteroid dependent, but it should be used only under specialist supervision. Thalidomide is teratogenic and, therefore, contra-indicated in pregnancy; it must not be given to women of child-bearing potential unless they comply with a pregnancy prevention programme. Increased doses of clofazimine are also useful. Paucibacillary leprosy should be treated with rifampicin and dapsone for 6 months. If treatment is interrupted the regimen should be recommenced where it was left off to complete the full course. Neither the multibacillary nor the paucibacillary antileprosy regimen is sufficient to treat tuberculosis. ANTIMYCOBACTERIALS › OTHER
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200 mg every 8 hours for 3 days
First-line fragment. Read the complete Indications and Dose section above.
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550 mg twice daily
First-line fragment. Read the complete Indications and Dose section above.
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