Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Moderiba. If you are concerned about side effects, discuss the risks and benefits of Moderiba with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• tiredness
• low red blood cells (anemia)
• headache
• difficulty sleeping
• itching
• nausea

In addition to the side effects noted above, other common side effects when this medication is taken in combination with both sofosbuvir and peginterferon include low white blood cells and nausea.

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

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

• signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of bleeding (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don’t stop bleeding)
• signs of infection (symptoms may include Fever or chills, severe Diarrhea, shortness of breath, prolonged dizziness, cough, headache, stiff neck, weight loss, or listlessness)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., rash; Hives; swelling of the face, mouth, lips, throat, and tongue; difficulty swallowing or breathing)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Moderiba.

200 mg
Each light blue, capsule-shaped, film-coated tablet, debossed with "200" on one side and the logo "3RP" on the other side, contains ribavirin 200 mg. Nonmedicinal ingredients: carnauba wax, croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, partially hydrolyzed polyvinyl alcohol, Polyethylene Glycol 3350, povidone, talc, titanium dioxide, and indigo carmine aluminum lake.

400 mg
Each medium blue, capsule-shaped, film-coated tablet, debossed with "400" on one side and the logo "3RP" on the other side, contains ribavirin 400 mg. Nonmedicinal ingredients: carnauba wax, croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, partially hydrolyzed polyvinyl alcohol, polyethylene glycol 3350, povidone, talc, titanium dioxide, and brilliant blue FCF aluminum lake.

600 mg
Each dark blue, capsule-shaped, film-coated tablet, debossed with "600" on one side and the logo "3RP" on the other side, contains ribavirin 600 mg. Nonmedicinal ingredients: carnauba wax, croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, partially hydrolyzed polyvinyl alcohol, polyethylene glycol 3350, povidone, talc, titanium dioxide, and brilliant blue FCF aluminum lake.

Do not use ribavirin if you:

• are allergic to ribavirin or any ingredients of Moderiba
• are pregnant or planning to become pregnant
• have a female partner who is pregnant or planning to become pregnant
• have a blood disorder (e.g., thalassemia or sickle-cell Anemia)
• are taking the medication didanosine

There may be an interaction between ribavirin and any of the following:

• abacavir
• alfa interferons (e.g., interferon alfa-2B)
• Azathioprine
• didanosine
• emtricitabine
• entecavir
• Influenza virus vaccine
• lamivudine
• stavudine
• zidovudine

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Moderiba. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Blood tests: Your doctor may recommend that you have blood tests regularly while you are taking Moderiba.

Heart problems: If you have heart problems, discuss with your doctor how Moderiba may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Moderiba, and whether any special monitoring is needed.

Kidney function: If you have reduced kidney function or Kidney Disease, discuss with your doctor how Moderiba may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Moderiba, and whether any special monitoring is needed.

Pregnancy: Ribavirin can cause serious birth defects. Do not use Moderiba if you are pregnant or planning to become pregnant. If you have a female partner, do not use Moderiba if she is pregnant or planning to become pregnant. While taking Moderiba and for 6 months after stopping the medication, use two reliable forms of birth control (one for each partner). This applies to women taking ribavirin as well as female partners of men taking ribavirin. Contact your doctor immediately if a pregnancy occurs while you or your partner are taking Moderiba or within 6 months after the medication is stopped.

Breast-feeding: It is not known if ribavirin passes into breast milk. If you are a breast-feeding mother and are using Moderiba, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of Moderiba for children younger than 18 years of age have not been established.

Seniors: Seniors may have a higher risk of side effects from Moderiba.