Precautions
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.
Using peginterferon alfa-2a together with ribavirin while you are pregnant can harm your unborn baby. These medicines may also cause birth defects if the father is using it when his sexual partner becomes pregnant. If a pregnancy occurs while you are using these medicines, tell your doctor right away. Your doctor may want you to join a pregnancy registry for patients taking this medicine with ribavirin.
A negative pregnancy test is needed for women who are of childbearing age before starting treatment with this medicine and ribavirin. Two forms of birth control must be used during treatment and for 6 months after treatment ends. You will need to have pregnancy tests done every month while you receive these medicines and after your treatment ends.
This medicine contains benzyl alcohol which may cause serious reactions to newborn or premature infants. Discuss this with your doctor if you are concerned.
You should not use this medicine if you are also taking didanosine (Videx®, Videx® EC) while you are using this medicine. Using these medicines together may cause serious problems.
This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you, your child, or your caregiver notice any of these side effects, tell your doctor or your child's doctor right away.
This medicine may cause serious types of allergic reactions, including anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Stop using this medicine and call your doctor right away if you have itching, hives, hoarseness, trouble with breathing, trouble with swallowing, or any swelling of the hands, face, or mouth while you or your child are using this medicine.
Serious skin reactions can occur with this medicine. Stop using this medicine and check with your doctor right away if you have blistering, peeling, or loosening of the skin; fever or chills; hives or welts; red skin lesions; a severe skin rash or acne; or sores or ulcers on the skin while you or your child are using this medicine.
This medicine will not keep you from giving hepatitis B or hepatitis C to other people.
This medicine combined with ribavirin can temporarily lower the number of white blood cells in your blood, which will increase the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:
- If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
- Check with your doctor immediately if you notice any unusual bleeding or bruising; black, tarry stools; blood in the urine or stools; or pinpoint red spots on your skin.
- Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
- Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
- Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
- Avoid contact sports or other situations where bruising or injury could occur.
Check with your doctor right away if you or your child have back, leg, or stomach pains; bleeding gums; chills; dark urine; difficulty breathing; fever; general body swelling; headache; loss of appetite; nausea or vomiting; nosebleeds; pale skin; sore throat; unusual tiredness or weakness; or yellowing of the eyes or skin. These could be symptoms of a blood disorder called anemia.
Stop using this medicine and check with your doctor right away if you or your child have symptoms that could lead to pancreatitis. This includes sudden and severe stomach pain, chills, constipation, nausea, vomiting, fever, or lightheadedness.
Check with your doctor immediately if blurred vision, difficulty in reading, eye pain, or any other change in vision occurs during or after treatment. Your doctor may want you or your child to have your eyes checked by an ophthalmologist (eye doctor).
Peginterferon alfa-2a used together with ribavirin may affect your child's growth. Your doctor may need to check your child's height and weight during and after treatment with these medicines.
Peripheral neuropathy may occur if you use this medicine together with telbivudine (Tyzeka®). Check with your doctor right away if you or your child are having burning, numbness, tingling, or painful sensations in the arms, hands, legs, or feet.
This medicine may cause some people to become drowsy, dizzy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy and not alert.
Avoid drinking alcohol (including beer, wine, or liquor) while you are using this medicine.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.


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