Managing side effects of interferon-beta in patients with relapsing-remitting multiple sclerosis

In separate clinical trials, two preparations of recombinant interferon (IFN)-beta, IFN beta-la and IFN beta-lb, reduced exacerbation rates in relapsing-remitting multiple sclerosis (RR-MS). Further, IFN beta-la slows the progression of disability in patients with RR-MS. Although they are effective in the treatment of MS, use of these drugs is associated with both class-specific and agent-specific side effects. Class-specific side effects include fever, chills, myalgias, arthralgias, and other flulike symptoms beginning 2 to 6 hours after injection and resolving within 24 hours of injection. Transient worsening of preexisting MS symptoms also occurs infrequently. Agent-specific side effects include injection-site reactions with IFN beta-lb. Simple management strategies can be used to minimize these reactions, including patient education; tailoring the dose and time of administration of IFN-beta; and prescribing appropriate combinations of acetaminophen, nonsteroidal anti-inflammatory drugs, and steroids. Although side effects tend to diminish with treatment, successful management allows long-term administration of these drugs to achieve a reduction in disease activity and commensurate improvement in outcomes.