Drug InteractionsPeginterferon alfa-2a may react with several other medications (see Drug Interactions With Peginterferon Alfa-2a).
What If I Overdose on This Medicine?People who use too much peginterferon alfa-2a might experience side effects that are more severe than normal. If you think you may have overdosed on this medication, seek immediate medical attention.
(Click Pegasys Overdose for more information.)
What If I Miss a Dose of Peginterferon Alfa-2a?If you miss a dose of peginterferon alfa-2a, call your healthcare provider for further instructions.
How Does It Work?Peginterferon alfa-2a is a manufactured version of interferon and is almost identical to a naturally occurring human interferon. Interferons are naturally occurring proteins or glycoproteins (proteins attached to carbohydrates). In humans, interferons are produced by cells in response to certain situations, such as viral infections, and often play a key role in the immune system.
When given as medications, interferons do not last very long in the body. To get around this problem, peginterferon alfa-2a was made by attaching each interferon to a molecule of polyethylene glycol. This makes the medication last much longer, allowing for once-a-week dosing. Because peginterferon alfa-2a is a protein, it would be broken down and destroyed by the digestive system if taken by mouth. For this reason, the drug must be injected to bypass the digestive tract.
Peginterferon alfa-2a works to fight hepatitis B and C by activating the body's own response to viruses.