BOB HIRSHON (host):
Your drugs on sunlight…I’m Bob Hirshon and this is Science Update.
Sunlight boosts your vitamin D levels. But that, in turn, may make certain medications less effective. This according to researchers at the Karolinska Institute in Sweden. Clinical pharmacologist Jonatan Lindh and his colleagues studied more than seventy thousand blood tests from transplant patients, who were taking immune-suppressing drugs.
JONATAN LINDH (Karolinska Institute, Sweden):
The drug concentrations were significantly lower during the period of high vitamin D levels. That would be in the late summer and early autumn.
That’s compared to late winter, when vitamin D levels are lowest. It’s believed that vitamin D boosts an enzyme that breaks down these and many other drugs. Lindh says the effect is subtle and may be relevant only in certain cases. Even then, he says adjusting the dose would be better than avoiding the sun. I’m Bob Hirshon, for AAAS, the science society.