Q. Though lidocaine patches help with my chronic headache pain, they can be cumbersome to apply. My local pharmacists are in disagreement: One said patches cannot be cut, but the other said I could cut my lidocaine patch to a size more suitable to my needs. Who is correct?

A. As a general rule, medication patches should not be cut or otherwise altered. Cutting the patch could increase the absorption of the drug, which could increase side effects, deplete the patch’s medication too quickly and cause other problems.

Lidocaine patches are, to my knowledge, the only exception to that general rule. A lidocaine patch’s dimensions are approximately four inches by six inches, which is rather large to place on a forehead (the location used by most patients). With a pair of scissors, patients can cut the patch to an appropriate size prior to applying to their forehead or other hairless area. Typically, patches are left on for 12 hours, then removed for 12 hours prior to applying another patch.

Richard Wenzel, PharmD
Diamond Headache Clinic
Chicago, IL