Currently, 5 injectable medications are approved in the US as being safe and effective for MS to reduce relapses and risk of progressive disability. Several pill therapies are also sometimes used. Three injections are different forms of interferon-beta, a hormone used by the body to defend against viruses. One injection is an artificial protein which alters the immune response, much like an allergy shot. The other medications are stronger medications to diminish the action of the immune cells.
Weekly low dose interferon or Avonex, protects against more severe relapses and reduces time to the next relapse, especially early in the course of the disease prior to an established course of MS. Betaseron and Rebif, both multiple doses weekly of interferon, have better effect in established MS and in those with a progressive as well as relapsing component to illness. Interferons have similar side effects which resemble the symptoms of a virus. Usually these adverse symptoms diminish with each injection, cause no harm, and can mostly prevented by analgesics such as acetaminophen, ibuprofen, and naproxen. Although these medications are very safe, occasional individuals have stress on their blood or liver, requiring blood tests to monitor for this problem. Individuals usually administer these injections on their own, often with an automatic injector, although some may receive the weekly interferon in the doctor’s office.
Copaxone, a noninterferon the allergy shot therapy, is an alternative medication to the interferons but takes 6-12 months to reach its greatest effectiveness. It has benefits on relapses and some improvement on MRI activity. Generally, the effect on MRI is not as great as that with interferons. It is however extremely safe and has virtually no side effects other than at sites of injection.
Powerful immunosuppressive medications are used for more difficult courses of MS. These include Novantrone, an approved chemotherapy agent. This drug is well tolerated but increases risks of infection, but more reliably produces improvement than any other treatment. Azathioprine and methotrexate are immunosuppressive medications available as pills, but have been used successfully alone and in combination with other therapies to improve the course of MS. These medications are rarely used as first choices in therapy due to the increased risk associated with them, and careful consideration is warranted with counseling from the physician.