An increasing frequency of misuse and abuse of biological drugs such as hallucinogenic mushrooms and various plants containing tropane alkaloids was found among young German multiple drug addicts. In this drug rehabilitation center 180 patients were questioned about their drug habits and more then 50% admitted to have experience with biological drugs. We want to inform about this phenomenon which we observed during recent years.These drugs lead to new forms of intoxication, including psychotic and aggressive phases. The practice of abuse and the clinical and medico-legal concequenses of ingestion of these drugs are discussed. Keywords Biological drugs · Psilocybe · Amanita · Datura