Mismatch Between Timing of Medications and Circadian Rhythms Might Alter Drug Effectiveness

Circadian rhythms are governed not only by a master regulator in the brain but also by organs, tissues, and cells that have their own circadian rhythms, which “talk” back and forth with the master regulator. A new study shows that this complex process might have important effects on pharmacotherapy.

U.S. investigators looked for circadian patterns in the activation (expression) of genes in 12 different organs and tissues in mice. They measured the extent to which each of nearly 20,000 mouse genes was expressed in each organ or tissue at different times during the 24-hour day. Forty-three percent of these protein-coding genes showed circadian variation. Of potential importance to medical practice, more than half of the 100 best-selling drugs …