About DMARDs

DMARDs (disease-modifying anti-rheumatic drugs) are a group of medications used to treat rheumatoid arthritis and other auto-immune diseases, including ankylosing spondylitis, lupus and psoriatic arthritis. Unlike other treatments for these conditions, DMARDs alter the course of the disease and are quite useful in preventing or reducing further damage to the body. DMARDs are not a specific drug class, but are treated as such when used for auto-immune disorders.

Function

DMARDs are used as a second-line treatment, when first-line treatments such as high-dose aspirin and NSAIDs fail to provide sufficient relief. Auto-immune disorders are caused when the immune system attacks healthy cells in the body, and DMARDs are effective in modifying immune response to prevent the body from damaging itself. In certain auto-immune disorders, particularly lupus, DMARDs may be used as soon as a diagnosis is made. This is because the risk of organ damage from lupus and certain other disorders is great enough to justify their use even when symptoms are not especially severe. Depending on which DMARD is prescribed, NSAID therapy may be continued during treatment.

Types

Several DMARDs are used to treat auto-immune disorders and most are vastly different drugs. Gold salts have been used to treat rheumatoid arthritis for the last half-century, when a patient was given this treatment for tuberculosis only to find that his arthritis improved instead. Penicillamine, despite the name, is not an antibiotic but rather an immuno-modulatory drug. Hydroxycholoroquine (Plaquenil) is a drug used to treat malaria that also functions as a DMARD. It is favored because of its relatively low risk of severe side effects. Methotrexate is perhaps the most effective of the DMARDs and is widely prescribed for rheumatoid arthritis; this drug is also used to treat breast cancer. Sulfasalazine is a drug primarily used to treat inflammatory bowel disease, although it has also been used with some success in rheumatoid arthritis.

Considerations

DMARDs usually provide considerable relief from symptoms and slow the progression of auto-immune diseases, although they cannot be expected to lead to full remission in most people. Most DMARDs are effective in between 30 and 50 percent of patients, so it is not uncommon to need to try several different DMARDs before finding one that works well and has tolerable side effects. With the exception of methotrexate, DMARDs typically take 4 to 6 months to produce significant relief. Methotrexate acts much more quickly and often produces noticeable relief from symptoms within a few weeks. However, this particular medication can have severe side effects and almost always causes miscarriage in women who take the drug in early pregnancy.

Effects

All DMARDs are believed to work in basically the same way--by inhibiting the function of white blood cells that attack healthy tissue as a result of a malfunctioning immune system. DMARDs are associated with a wide variety of side effects, some of which can be quite severe. Because DMARDs interfere with the immune system, most of them are associated with an increased risk of infection and more severe infections. Other side effects shared by two or more DMARDs include ulcers in the mouth, vomiting, nausea, diarrhea and liver damage. Hydroxycholoroquine is the least likely of the DMARDs to cause problematic side effects, and for this reason it is often the first drug of its type attempted.

Time Frame

DMARDs are taken as maintenance medications, which means that they are taken on a regular schedule for an indefinite period of time. Most people who require DMARDs in the treatment of auto-immune disorders will need to take the medication for the rest of their lives, or until it is replaced by an even stronger drug to treat more severe symptoms. Dosage schedules vary considerably, and may be as frequent as four times daily (hydroxycholoroquine) or as infrequent as once weekly (methotrexate).

Resources

• The Facts of DMARDs
• WebMD: DMARDs
• UpToDate: DMARD Information for Patients