Common uses

Rebetol capsules have been approved as a separately marketed product for use in combination with Intron A (interferon alfa-2b) injection. This drug is designed as a treatment for chronic hepatitis C in patients with compensated liver disease who have not had previous alpha interferon therapy or who have relapsed following successful therapy.
Rebetol has been approved in the United States since 1998 as part of a single-package combination therapy (known as Rebetron) that includes Rebetol capsules and Intron A injection. The new stand-alone package of Rebetol capsules provides patients and physicians with the option of individualized ribavirin and interferon-based therapies.

Before using

You should not take this medication if you are allergic to ribavirin, or if you have:
• severe liver disease;
• autoimmune hepatitis;
• a hemoglobin disorder such as anemia, thalassemia (Mediterranean anemia), or sickle-cell anemia; or
• if you are pregnant woman, or a man whose female sexual partner is pregnant.
Before using Rebetol, tell your doctor if you are allergic to any drugs, or if you have:
• kidney or liver disease;
• hepatitis B infection;
• a blood cell disorder;
• cancer;
• psoriasis;
• diabetes;
• sarcoidosis;
• a thyroid disorder;
• hepatitis B virus or human immunodeficiency virus (HIV or AIDS);
• a history of heart disease, high blood pressure, or a heart attack;
• a history of depression or suicide attempt;
• a history of drug or alcohol addiction; or
• a history of a liver or other organ transplant.
• Tell your doctor if you have been treated with interferon in the past and it did not work well in treating your hepatitis C.

Directions

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.
Rebetol is not effective when used alone to treat hepatitis C. It must be used together with an interferon alfa product (such as Peg-Intron or Intron A) to treat chronic hepatitis C. Take this medicine with food.
Measure the liquid form of Rebetol with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.
Rebetol may decrease the number of red blood cells in your body. This is called anemia and it can be life-threatening in people who have heart disease or circulation problems. To be sure this medication is not causing harmful effects, your blood will need to be tested on a regular basis. Your liver and thyroid function may also need to be checked. Do not miss any scheduled visits to your doctor.
Call your doctor at once if you have pale or yellowed skin, dark colored urine, fever, confusion, chest pain, shortness of breath, or weakness. These may be signs of serious anemia.
It is important to use Rebetol regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely. You may need to take this medication for many months.
Drink extra fluids while you are taking Rebetol to keep from getting dehydrated, especially during exercise or in hot weather.
Rebetol can cause dry mouth, which could lead to tooth decay or gum disease. If you vomit while taking Rebetol, rinse your mouth out with water to prevent damage to your teeth or gums. Be sure to have regular dental exams while you are taking this medication.
Store Rebetol tablets and capsules at room temperature away from moisture, heat, and light. Store ribavirin liquid (oral solution) in the refrigerator. Do not allow it to freeze.

Cautions

Based on results of clinical trials ribavirin monotherapy is not effective for the treatment of chronic hepatitis C virus infection; therefore, Rebetol Capsules or Oral Solution must not be used alone. The safety and efficacy of Rebetol Capsules and Oral Solution have only been established when used together with Intron A as a combination therapy or with PegIntron Injection.
There are significant adverse events caused by Rebetol or PegIntron therapy, including severe depression and suicidal ideation, hemolytic anemia, suppression of bone marrow function, autoimmune and infectious disorders, pulmonary dysfunction, pancreatitis, and diabetes. Suicidal ideation or attempts occurred more frequently among pediatric patients, primarily adolescents, compared to adult patients (2.4% versus 1%) during treatment and off-therapy follow-up. The INTRON A and PegIntron package inserts should be reviewed in their entirety prior to initiation of combination treatment for additional safety information.

Possible side effects

Side effects associated with Rebetol include (but are not limited to) the following:
• Anemia
• Fatigue
• Nausea
• Rash
• Itching
Individuals with a history of significant or unstable heart disease should not use Rebetol capsules, as fatal and non-fatal heart attacks have occurred in patients with anemia caused by the drug.
Additionally, due to the possibility of severe adverse events, extreme care must be taken to prevent pregnancy in female patients receiving Rebetol and female partners of male patients.
Serious side effects due to Intron A use may include the following:
• Severe depression
• Psychoses
• Aggressive behavior
• Hallucinations
• Decrease in white blood cells

If you take too much

Seek emergency medical attention if you think you have used too much of this medicine. Overdose symptoms may include easy bruising or bleeding, urinating less than usual or not at all, chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, or a general ill feeling.

Additional information

Treatment with Rebetol does not prevent spread of the hepatitis C virus to other people. Follow your doctor's instructions about how to prevent passing the disease to another person.
Do not drink alcohol while taking Rebetol. Alcohol can increase the risk of damage to your liver. Rebetol can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Drug interactions

Before taking Rebetol, tell your doctor if you are using any of the following drugs:
• abacavir (Ziagen);
• didanosine (Videx);
• lamivudine (Combivir, Epivir, Epzicom, Trizivir);
• stavudine (Zerit);
• tenofovir (Viread);
• zalcitabine (Hivid); or
• zidovudine (Retrovir, AZT).
This list is not complete and there may be other drugs that can interact with Rebetol. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication