Timed treatment of the arthritic diseases: a review and hypothesis

Evidence has been accumulating regarding the importance of biological rhythms in the diagnosis and treatment of a variety of diseases and disorders. Increasingly, the arthritides have shown statistically quantifiable rhythmic parameters. Included in the latter group are joint pain and joint size. In addition, a number of drugs used to treat rheumatic diseases have varying therapeutic and toxic effects based on the time of day of administration. Among these drug classes are nonsteroidal antiinflammatory drugs, glucocorticoids, and a number of cytostatic agents. In the last group of agents, experience in treating malignant disease suggests that time-specified treatment may reduce the toxic effects of low-dose cytostatic treatment of rheumatoid arthritis (RA) and related diseases. This article reviews that evidence and suggests a rationale for the timed treatment of RA with methotrexate.