In brief: Split decision
Cost-conscious patients have been splitting their pills for years. Although they officially object, pharmaceutical companies invite the practice with "flat pricing," which means a 20-mg pill costs the same as a 40-mg one. The math is easy: Don't waste your money on the 20-mg pills; cut the 40-mg pill in half. You're effectively getting two doses for the price of one.
Until recently, pill splitting has been an individual, homespun sort of operation. A steady hand, a flat surface, and a sharp razor blade was all you needed, although most drugstores now sell little guillotine-like devices for a few dollars that make it easier because they hold the pill steady for you.