Caffeine enhances and accelerates the expression of sensitization induced by coca paste indicating its relevance as a main adulterant

Abstract

Results may shed light on the fast and high dependence observed in CP users.

Caffeine, a common active adulterant of cocaine, enhances the reinforcing effect of cocaine and its motivational value

“…Exposure to caffeine increases the psychomotor stimulant effects of amphetamine (Cauli et al 2003;Palmatier et al 2003;Simola et al 2006), nicotine (Celik et al 2006;Gasior et al 2000), and cocaine (López-Hill et al 2011;Misra et al 1986;Prieto et al 2015). However, this effect does not explain our results since the increase in responding of the coc + caff group was restricted to the active nosepoke, whereas inactive nosepoke responding remained low at all times.…”

“…Cocaine doses were chosen based on previous data (Valentini et al 2013). Caffeine doses were selected to mimic a dose ratio found in seized samples of cocapaste (López-Hill et al 2011;Prieto et al 2015) or in other street samples as reported in literature (see an overview at http://www.drugsandalcohol.ie/13119/).…”

“…Adulterant refers to pharmacologically active ingredients while diluents refer to inert substances. Several forensic studies have reported that caffeine is one of the most common psychoactive adulterants found in illicit drugs of abuse (Cole et al 2011) such as cocaine, either in its snorted (hydrochloride) or smoked forms (cocapaste or crack) (Evrard et al 2010;López-Hill et al 2011;Prieto et al 2015). Caffeine is believed to be added to increase the weight and volume but also to mimic or potentiate the psychostimulant and the reinforcing effects of cocaine.…”

“…In animal studies, it was demonstrated that caffeine is able to potentiate several effects of cocaine. For example, caffeine potentiates the motor stimulation induced by cocaine (Misra et al 1986;López-Hill et al 2011;Prieto et al 2012) as well as the expression of cocaine-or amphetamine-elicited sensitization (Cauli et al 2003;Simola et al 2006;Prieto et al 2015). An additive reinforcement effect of caffeine with cocaine was observed in a conditioned place preference paradigm (Bedingfield et al 1998).…”

“…In addition, the role of caffeine as a primer cue during extinction was evaluated. We also considered a ratio of doses found in street samples of cocaine (López-Hill et al 2011;Prieto et al 2015). To our knowledge, this is the first study that investigates the effect of caffeine on the rewarding properties of cocaine under a progressive ratio schedule of reinforcement and in a condition where caffeine is co-administered with cocaine.…”