When Over-the-Counter Painkillers Aren't Effective

Q. I take an over-the-counter painkiller for occasional backaches. Sometimes it works wonderfully, other times it doesn't do much. Why could this be?

Dr. Marianne Legato: How well these drugs work can depend on where you are in your menstrual cycle, since changing hormone levels affect the speed with which drugs enter and leave the bloodstream. Toward the end of your cycle, when estrogen and progesterone peak and then plummet, drug metabolism happens most quickly and you may find that you have to take more frequent doses of medication to ease your headache. Fluctuating hormones also affect your experience of pain. Estrogen, which is at its highest mid-cycle, makes your perception of pain less intense, while low levels in the days just before your period may make you more pain-sensitive.

Marianne Legato, MD, medical adviser to Ladies' Home Journal, is the founder and director of the Partnership for Gender-Specific Medicine at Columbia University.

Originally published in Ladies' Home Journal magazine, February 2006.

Do you have a health question, concern, or worry? E-mail your questions to Dr. Legato at AskDrLegato@lhj.com, and the answer (but not your name) may be featured in an upcoming issue of Ladies' Home Journal or on LHJ.com.