A hypnotic is a drug that triggers sleep. In common parlance, they are called sleeping pills. Various molecules have hypnotic effects such as barbiturates, which are less commonly used, and benzodiazepines, or benzodiazepine related molecules. Due to their side-effects, these drugs should be taken with caution, especially when driving. These molecules are not without side-effects and can induce addiction or dependence. Hypnotics should not be taken for long periods and should only be used to help get through a difficult period.