Etanercept

Injection site reactions (localized redness and itching) may occur with etanercept or adalimumab, while infusion reactions (hives or less commonly shortness of breath) may be seen with infliximab. All of these medications have been associated with an increased rate of respiratory infections and may render patients more prone to other types of infections as well. Individuals with prior exposure to tuberculosis have experienced recurrences and disseminated disease in clinical studies. Patients with pre-existing multiple sclerosis or advanced congestive heart failure should not take these drugs, as they have been associated with worsening of these diseases. Rare side effects include lowered blood counts, elevated liver enzymes, and drug-induced lupus. Thus far, studies have failed to demonstrate a link between use of these drugs and solid cancers. Some concern exists as to an increased risk of lymphoma, which is difficult to document, as having rheumatoid arthritis also increases one’s risk for lymphoma.

A baseline tuberculin skin testing or prior skin test within one year of starting therapy is recommended. While no specific guidelines are in place, monitoring blood counts every 3-6 months and liver function tests every 6-12 months is reasonable.