What side effects can this medication cause? 

Ribavirin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• cough
• upset stomach
• vomiting
• diarrhea
• constipation
• heartburn
• loss of appetite
• weight loss
• changes in ability to taste food
• dry mouth
• difficulty concentrating
• difficulty falling asleep or staying asleep
• memory loss
• rash
• dry, irritated, or itchy skin
• sweating
• painful or irregular menstruation (period)
• muscle or bone pain
• hair loss

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, or those listed in the IMPORTANT WARNING section, call your doctor immediately:

• hives
• swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• hoarseness
• difficulty swallowing or breathing
• pain in the stomach or lower back
• bloody diarrhea
• bright red blood in stools
• black, tarry stools
• unusual bleeding or bruising
• vision changes
• fever, chills, and other signs of infection
• depression
• thinking about hurting or killing yourself
• mood changes
• excessive worry
• irritability
• starting to use street drugs or alcohol again if you used these substances in the past
• worsening of psoriasis that you had before you started to take ribavirin
• intolerance to cold

Ribavirin may slow growth and weight gain in children. Talk to your child's doctor about the risks of giving this medication to your child.

Ribavirin may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.