Rifaximin

Rifaximin is a prescription medication used to treat traveler’s diarrhea and irritable bowel syndrome with diarrhea. It is also used to reduce the recurrence of hepatic encephalopathy in adults. Rifaximin should not be used if diarrhea is accompanied by fever or blood in the stool.

Rifaximin belongs to a group of drugs called antibiotics. These work by stopping the growth of bacteria that cause diarrhea and by stopping the growth of bacteria that produce toxins that worsen liver disease.

This medication comes in tablet form and is taken 2 to 3 times a day, depending on the indication. It can be taken with or without food.

Common side effects of rifaximin include headache, swelling of the extremities, nausea, dizziness, and fatigue.

Rifaximin can also cause dizziness. Do not drive or operate heavy machinery until you know how rifaximin affects you.

Rifaximin is a prescription medication used to treat traveler’s diarrhea caused by noninvasive strains of Escherichia coli and irritable bowel syndrome with diarrhea in adults and children at least 12 years old. It is also used to reduce the recurrence of hepatic encephalopathy in adults. Hepatic encephalopathy is a condition that causes changes in thinking, behavior, and personality caused by a build-up of toxins in the brain in people who have liver disease. Rifaximin should not be used if diarrhea is accompanied by fever or blood in the stool.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Rifaximin may be found in some form under the following brand names:

• Xifaxan

Serious side effects have been reported with rifaximin. See the "Rifaximin Precautions" section.

Common side effects of rifaximin include the following:

• nausea
• dizziness
• tiredness
• headache
• muscle tightening
• joint pain
• gas
• stomach pain
• feeling that you need to have a bowel movement
• fluid and swelling in the ankles, feet, and legs
• ascites (build-up of fluid in the space between the abdomen and abdominal organs)

This is not a complete list of rifaximin side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• other antibiotics
• verapamil (Calan, Covera-HS, Verelan)
• cyclosporine (Neoral, Sandimmune, Restasis, Gengraf)
• midazolam (Versed)
• oral contraceptives and hormone therapy containing estrogens such as ethinyl estradiol (Alesse, Ortho Tri-Cyclen, TriNessa, others)

This is not a complete list of rifaximin drug interactions. Ask your doctor or pharmacist for more information.

Serious side effects have been reported with rifaximin including the following:

• watery or bloody diarrhea that may be accompanied by stomach pain and fever during treatment or up to 2 months after treatment has stopped
• an allergic reaction, which could include symptoms such as hives, rash, itching, difficulty breathing or swallowing, hoarseness, and swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, and lower legs

Rifaximin can cause dizziness. Do not drive or operate heavy machinery until you know how rifaximin affects you.

Do not take rifaximin if you:

• are allergic to rifaximin or to any of its ingredients
• are allergic to any rifamycin antimicrobial agents including rifabutin (Mycobutin), rifampin (Rifadin, Rifamate, Rifater, Rimactane), and rifapentine (Priftin)

Medications can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of rifaximin, there are no specific foods that you must exclude from your diet when receiving this medication.

Before taking rifaximin, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

• are allergic to rifaximin or to any of its ingredients
• have liver problems
• are pregnant or breastfeeding

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans. Therefore, this medication may be used if the potential benefits to the mother outweigh the potential risks to the unborn child. Rifaximin may cause fetal harm. You and your doctor should decide if rifaxmin is safe for you to use during pregnancy.

Tell your doctor if you are breastfeeding or plan to breastfeed.

It is not known if rifaxmin crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using rifaximin.

Take rifaxmin exactly as prescribed.

Rifaximin comes in tablet form and is taken 2 to 3 times daily.

It may be taken with or without food.

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of rifaximin at the same time.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

• the condition being treated
• other medical conditions you have
• other medications you are taking
• how you respond to this medication

The recommended dose of rifaximin for the treatment of traveler’s diarrhea is 200 mg 3 times daily for 3 days.

The recommended dose of rifaximin for the treatment of irritable bowel syndrome with diarrhea is 500 mg 3 times daily for 14 days.

The recommended dose of rifaximin for the prevention of hepatic encephalopathy is 550 mg 2 times daily.

If you take too much rifaximin, call your healthcare provider or local Poison Control Center, or seek emergency medical attention right away.

If rifaximin is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.

• Store rifaximin at room temperature.
• Keep this and all medicines out of the reach of children.