Contribution of Caffeine to the Psychostimulant, Neuroinflammatory and Neurotoxic Effects of Amphetamine-Related Drugs

Association of amphetamine-related drugs with beverages containing high levels of caffeine is becoming very popular among adolescents and young adults. This review by examining the psychostimulant properties and the neuroinflammatory and neurotoxic effects of this drug association provides a new vision of the risks correlated to multiple substances consumption. In preclinical studies, caffeine amplifies the effects of amphetamine-related drugs on behavioral parameters, such as locomotor activity, operant behavioral tests, and discriminative stimulus effects, and promotes long-term modifications in the brain. Preclinical data also demonstrate that caffeine contributes to increase the acute toxicity, seizures, hyperthermia, and tachycardia elicited by amphetamine-related drugs in rats. These effects, together with the results showing that caffeine potentiates the loss of central serotonin and dopamine and the induction of neuroinflammation by amphetamine-related drugs, emphasize that, depending on the conditions in which it is consumed, caffeine may amplify the effects of neurotoxic drugs