In the U.S.—

In Canada—

Another commonly used name is tribavirin.

• Antiviral, systemic

Ribavirin (rye-ba-VYE-rin) is used to treat severe virus pneumonia in infants and young children. It is given by oral inhalation (breathing in the medicine as a fine mist through the mouth), using a special nebulizer (sprayer) attached to an oxygen hood or tent or face mask.

Ribavirin taken by mouth (oral) treats a viral liver infection known as hepatitis C. It is used in combination with injectable interferon alfa-2b ( in-ter-FEER-on AL-fa-2b) or with injectable peginterferon alfa-2b (peg-in-ter-FEER-on AL-fa-2b) . Ribavirin is used to treat virus infections. Interferons are substances naturally produced by cells in the body to help fight infections and tumors. Interferon alfa-2b and peginterferon alfa-2b are synthetic (man-made) versions of these substances. Interferon alfa-2b and peginterferon alfa-2b are used to treat a variety of tumors and viruses including the hepatitis C virus.

Ribavirin is available in the following dosage forms:

Inhalation
• For inhalation solution (U.S. and Canada)

Oral
• Capsules (U.S.)
• Oral solution (U.S.)
• Tablets (U.S.)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For ribavirin, the following should be considered:

Allergies—Tell your doctor if you or your child has ever had any unusual or allergic reaction to ribavirin . Also tell your health care professional if you or your child is allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Ribavirin for inhalation is not usually prescribed for teenagers or adults. However, women who are pregnant or may become pregnant may be exposed to ribavirin that is given off in the air if they spend time at the child's bedside while ribavirin is being given. Although studies have not been done in humans, ribavirin has been shown to cause birth defects and other problems in certain animal studies. Be sure you have discussed this with your doctor.

Ribavirin for oral use should not be used while you are pregnant, if you plan on becoming pregnant, or by men whose female partners are pregnant or are planning to become pregnant. It has been shown to cause serious birth defects and other problems in animals. Be sure you have discussed this with your doctor.

Breast-feeding— It is not known whether ribavirin passes into human breast milk. However, ribavirin passes into the breast milk of animals and has been shown to cause problems in nursing animals and their young. It may be necessary for you to take another medicine or to stop breast feeding during treatment with ribavirin. Be sure you have discussed the risks and benefits of this with your doctor.

Children—Children may be sensitive to the effects of ribavirin. This may increase the chance of side effects or other problems during treatment. Be sure you have discussed the risks and benefits of this with your doctor.

Older adults—Many medicines have not been studied specifically in older people. Therefore it may not be known if they work the same way that they do in younger adults or if they cause different side effects or problems in older people than they do in younger adults.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking ribavirin it is especially important that your doctor and pharmacist know if you are taking any of the following:

• Didanosine (e.g., Videx)— this medicine should not be used at the same time as ribavirin because serious side effects can occur.

• Stavudine (e.g., Zerit) or
• Zidovudine (e.g., Retrovir)— these medicines should not be used at the same time as ribavirin

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

• Anemia (blood disorder) or
• Autoimmune hepatitis (liver inflammation)—Ribavirin could make these conditions worse and lead to very serious side effects.

• Heart disease—Patients with heart disease or a history of heart disease should not use ribavirin oral dosage forms because serious side effects can occur.

• Blood conditions such as
• Sickle Cell Anemia (red blood cell disorder) or
• Thalassemia major (genetic blood disorder)—Ribavirin should not be used in patients with these conditions.

• Hepatic decompensation—Ribavirin medicine should not be used in patients with this condition

• Mental depression—Ribavirin should be used carefully in patients with this condition, especially adolescents as serious side effects can occur

• Pancreatitis (inflammation of the pancreas)—Ribavirin should suspended in patients with symptoms of this condition and stopped in patients who have this condition

To help clear up your infection completely, ribavirin must be given for the full time of treatment, even if you or your child begins to feel better after a few days. Also, ribavirin for inhalation works best when there is a constant amount in the lungs. To help keep the amount constant, ribavirin must be given on a regular or continuous schedule.

It is important that you read the patient information that comes with this medicine. Ask your doctor if you have any questions.

A negative pregnancy test is needed in women who are of childbearing age before starting treatment with oral ribavirin. Two forms of birth control must be used during oral ribavirin treatment and for six months after treatment ends.

Dosing—

The dose of ribavirin will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of ribavirin. If your dose is different, do not change it unless your doctor tells you to do so.

• For the inhalation dosage form:
  • For treatment of respiratory syncytial virus (RSV) infection:
    • Adults and teenagers—Dose has not been determined since this medicine is not usually prescribed for teenagers or adults.
    • Infants and children—Dose must be determined by your doctor.

• For the oral dosage form:
  • For the treatment of HIV infection:
  • For oral dosage forms (capsules):
    • Adults and children—Dose must be determined by your doctor
  • For oral dosage form (oral solution):
    • Adults and teenagers—Dose must be determined by your doctor. The oral solution form of this medicine is not usually prescribed for teenagers or adults
    • Children—Dose must be determined by your doctor.
  • For oral dosage form (tablets):
    • Adults—Dose must be determined by your doctor.
    • Children— Use and dose must be determined by your doctor. The tablet form of this medicine is not usually prescribed for children

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly.

This medicine may cause some people to become dizzy, drowsy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, operate machinery or do anything else that could be dangerous if you are not alert.

It is very important that you stop this medicine and contact your doctor immediately if you think you might be pregnant.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• More common
  • Chest pain;  difficult or labored breathing ;  pale skin;  shortness of breath;  tightness in chest;  troubled breathing with exertion;  unusual bleeding or bruising;  unusual tiredness or weakness;  wheezing 
  
  

Along with its needed effects, a medicine may cause some unwanted effects. The following side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Acid or sour stomach;  belching;  discouragement;  dizziness;  feeling sad or empty;  feeling unusually cold;  heartburn;  indigestion ;  irritability;  itching skin;  lack of appetite;  loss of interest or pleasure;  lack or loss of strength ;  shivering;  stomach discomfort, upset, or pain;  tiredness;  trouble concentrating;  trouble sleeping 
  
  

• Less common
  • Change in taste;  cough;  crying;  depersonalization;  difficulty in moving;  dysphoria;  euphoria;  fatigue;  fever;  gastrointestinal effects;  headache;  insomnia;  joint pain;  mental depression;  muscle aching or cramping;  muscle pains or stiffness ;  nervousness;  pain or tenderness around eyes and cheekbones;  paranoia;  quick to react or overreact emotionally;  rapidly changing moods;  rash;  shortness of breath;  stuffy or runny nose;  swollen joints;  vomiting 
  
  

• Rare
  • Itching, redness, or swelling of eyes;  skin rash or irritation 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, ribavirin is used in certain patients with the following medical conditions:

• Influenza A and B (given by aerosol inhalation)
• Lassa fever (either given orally or by injection)

For patients taking this medicine by mouth or injection for Lassa fever:

• Check with your doctor immediately if any of the following side effects occur:
  More common
  • Unusual tiredness and weakness
• Other side effects may occur that usually do not need medical attention. The following side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:
  Less common
  • Headache; loss of appetite; nausea; trouble in sleeping; unusual tiredness or weakness

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for these uses.

This medicine may also be used for other virus infections as determined by your doctor. However, it will not work for certain viruses, such as the common cold.