Many people assume that medicines sold over the counter are inherently safe. After all, if you can buy something in a supermarket or high street pharmacy, how dangerous can it really be? The reality is more complicated. Several commonly used over-the-counter medicines carry a real risk of dependence, misuse, or harm when taken in higher than recommended doses, for longer than needed, or for the wrong reasons. Here are five medicines it is worth knowing about. 1. Codeine-based painkillers