The drugs with the highest risk for addiction and abuse fall into Penalty Group 1, while the substances in Penalty Group 4 have accepted medicinal purposes and present a lower risk of addiction. Cocaine, codeine, and heroin are common drugs in Penalty Group 1. Ecstasy and Valium are in Penalty Groups 2 and 3, respectively, while many over-the-counter medications are Penalty Group 4 drugs.