CUH Logo

Mobile menu open

Rifaximin (Targaxan®)

Patient information A-Z

Why rifaximin is prescribed

Rifaximin works by killing the bacteria which produce ammonia in your gut. Rifaximin reduces the risk of confusion (encephalopathy) caused by the build up of ammonia in your blood. This happens when your liver is not working properly.

Taking your rifaximin

There are two brands of rifaximin available, Targaxan® or Xifaxanta®. You should always receive the Targaxan® brand.

For patients with long-term liver problems the usual dose of rifaximin (Targaxan®) is 550mg (one tablet) twice a day.

You can take them with or without food. You usually take them long-term whilst you are prone to bouts of encephalopathy.

Problems to watch for

  • Make sure the name of your medicine is rifaximin (Targaxan®) Check the spelling very carefully when you get a new supply. If you are not sure, speak to your doctor or pharmacist.
  • You should not take rifaximin if you are allergic to it, or to antibiotics with a similar name such as rifampicin or rifabutin.
  • Rifaximin may affect sex hormonal contraceptives, hormone replacement therapy (HRT), or warfarin. If you are taking any of these medicines you should report this to your doctor or pharmacist.

Stop taking rifaximin immediately and tell your doctor if you experience the following:

  • bleeding from swollen blood vessels in your throat (oesophageal varices)
  • severe diarrhoea
  • unusual or unexpected bruising or bleeding

Side effects

Rifaximin can cause these side effects:

  • dizziness
  • headache
  • wind, bloating or pain in your tummy
  • constipation, diarrhoea or painful and ineffective straining
  • feeling or being sick
  • low mood
  • joint pain, muscle cramps, swelling of ankles, feet or fingers
  • rash or itching

Other side effects which can occur less often with rifaximin are:

  • yeast infections (such as thrush)
  • urinary infection
  • swelling or infection of your nose and throat, including sore or dry throat
  • loss of appetite or a strange taste in your mouth
  • loss of body fluid, frequent passing of urine
  • confusion, anxiety, sleeplessness or strange dreams
  • reduction in red blood cells
  • loss of concentration or loss of memory
  • reduced sense of touch
  • hot flushes
  • swelling due to too much fluid in the body (oedema)
  • urine to turn a reddish colour, contain blood, sugar or protein
  • fever
  • convulsions

Tell your doctor if these side effects occur.

Rifaximin and pregnancy

Rifaximin should be avoided during pregnancy. Women who are pregnant, planning to become pregnant or breast feeding should talk to their doctor before taking this medicine.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

Help accessing this information in other formats is available. To find out more about the services we provide, please visit our patient information help page (see link below) or telephone 01223 256998.

Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151