DRUG ABUSERS: Drugs are widely used by toxicomaniacs to reproduce drug effects. Drug abusers generally start with psychotrops, but other abuse drug classes. Toxicomanic behavior leads to addictive practices that are difficult to control. BARBITURATES: Both the oral and intravenous routes are used. The expected result is a state of ecstasy with a feeling of comfort. Intoxication may cause respiratory depression. Barbiturates induce physical and psychic dependence. Abuse is not widespread with this class of drugs. BENZODIAZEPINES: Drug abuses widely use benzodiazepines orally or intravenously. They search for a flash effect, with sedation and a feeling of comfort. All benzodiazepines induce physical and psychic dependence. Death may result from combinations leading to respiratory depression. Flunitrazepam is the most widely abused benzodiazepine in France. It induces serious neuropsychic disorders. ANTIDEPRESSANTS: Few are used, mostly at high doses. OPIATES: Administration gives the same effect as heroine injection. Opiates induce physical and psychic dependence. The adverse effects are similar to those of morphine with a higher risk of respiratory depression. AMPHETAMINES: Few are used, either orally or intravenously. They induce a flash with excitation, euphoria, and a period of invincibility. This is followed by a period of depression with risk of suicide. Psychic dependence is high. ANTICHOLINERGIC ANTIPARKINSONIANS: These drugs are well known to abusers for their hallucinatory effect. They induce atropinic adverse effects and physical and psychic dependence. GAMMA-HYDROXYBUTYRATE: This anesthetic is used for its euphoria and sedation effects. It may induce falling sickness or coma, with a risk of respiratory depression. KETAMINE: Administered via the intranasal route, ketamine induces a state of indifference. Death has been observed. ANABOLIC AND ANDROGENIC STEROIDS: These drugs are used for their physical and psychic stimulating effect. They induce potentially dangerous adverse effects such as cardiovascular, hepatic, neurological and psychiatric disorders. Clinical signs of addiction and weaning are observed. OTHERS: Several other drug classes are used by abusers, including analgics, beta-adrenergic agents, nasal vasoconstrictors and corticosteroids.