By the way, doctor: Do airport x-rays affect medications?

Q. I travel frequently and always carry my estrogen and thyroid pills with me. Could the radiation from airport security alter them or make them less effective?

A. Most medications are not affected by the low doses of radiation emitted by airport screening machines, even if they're exposed several times in a trip. Certain drugs called "biologics," which include insulin and red blood-cell boosters such as epoetin alfa injection (Epogen, Procrit, and others) require special handling and storage; travelers sometimes worry about putting them through the x-ray machine. But according to the FDA's Center for Biologics, any harmful effects from x-rays on these medications would occur only at doses that are "orders of magnitude higher" than the radiation received from x-ray screening devices.