This guide serves to inform you of the different types of Drug tests available, what type of test to choose, and under which circumstances. Drugs can be divided into legally prescribed drugs like: Benzodiazepines (E.g. Valium), Opiates and other Analgesics, and Illicit drugs like: Amphetamines, Vocaine and Marijuana. Prescription drugs are often abused and can also be obtained illicitly. Individuals who are abusing drugs display clinical signs that are associated with the drug of abuse.