HOW should this medicine be used?
Peginterferon alfa-2a comes as a solution (liquid) in a vial, a prefilled syringe, and a disposable autoinjector to inject subcutaneously (into the fatty layer just under the skin). It is usually injected once a week, on the same day of the week, and at around the same time of day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use peginterferon alfa-2a exactly as directed. Do not use more or less of this medication or use it more often than prescribed by your doctor.
Your doctor will probably start you on an average dose of peginterferon alfa-2a. Your doctor may decrease your dose if you experience serious side effects of the medication. Be sure to tell your doctor how you are feeling during your treatment and ask your doctor or pharmacist if you have questions about the amount of medication you should take.
Continue to use peginterferon alfa-2a even if you feel well. Do not stop using peginterferon alfa-2a without talking to your doctor.
Only use the brand and type of interferon that your doctor prescribed. Do not use another brand of interferon or switch between peginterferon alfa-2a in vials, prefilled syringes, and disposable autoinjectors without talking to your doctor. If you switch to a different brand or type of interferon, your dose may need to be changed.
You can inject peginterferon alfa-2a yourself or have a friend or relative give you the injections. Before you use peginterferon alfa-2a for the first time, you and the person who will be giving the injections should read the manufacturer's information for the patient that comes with it. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to inject it. If another person will be injecting the medication for you, be sure that he or she knows how to avoid accidental needlesticks to prevent the spread of hepatitis.
You can inject peginterferon alfa-2a anywhere on your stomach or thighs, except your navel (belly button) and waistline. Use a different spot for each injection. Do not use the same injection spot two times in a row. Do not inject peginterferon alfa-2a into an area where the skin is sore, red, bruised, scarred, infected, or abnormal in any way.
If you do not receive the full prescribed dose because of a problem (such as leakage around the injection site), call your doctor.
Never reuse syringes, needles, or vials of peginterferon alfa-2a. Dispose of used needles and syringes in a puncture-resistant container. Talk to your doctor or pharmacist about how to dispose of the puncture-resistant container.
Before you use peginterferon alfa-2a, look at the solution in the vial, prefilled syringe, or autoinjector closely. Do not shake vials, syringes, or autoinjectors containing peginterferon alfa-2a. The medication should be clear and free of floating particles. Check the vial or syringe to make sure there are no leaks and check the expiration date. Do not use the solution if it is expired, discolored, cloudy, contains particles, or is in a leaky vial or syringe. Use a new solution, and show the damaged or expired one to your doctor or pharmacist.