Caffeine as an adulterant of coca paste seized samples: preclinical study on the rat sleep–wake cycle

Abstract

Caffeine is a common active adulterant found in illicit drugs of abuse, including coca paste (CP). CP is a smokable form of cocaine mainly consumed in South America, produced during the cocaine-extraction process. CP has high abuse liability and its chronic consumption induces severe sleep-wake alterations. However, the effect of CP on the sleep-wake cycle and the effect of the presence of caffeine as an adulterant remain unknown. We studied the effect of an acute intraperitoneal injection of 2.5 and 5 mg/kg of a representative CP sample adulterated with caffeine (CP1) on the rat sleep-wake cycle. Compared with saline, administration of CP1 induced an increase in wakefulness and a decrease in light (light sleep) and slow wave sleep that was larger than the effects produced by equivalent doses of cocaine. Compared with CP1, combined treatment with cocaine (5 mg/kg) and caffeine (2.5 mg/kg), a surrogate of CP1, elicited similar effects. In contrast, a nonadulterated CP sample (CP2) produced an effect that was not different from cocaine. Our data indicate that caffeine produces a significant potentiation of the wakefulness-promoting effect of cocaine, suggesting that caffeine should be explored as a causal agent of clinical symptoms observed in CP users.

Simultaneous administration of cocaine and caffeine dysregulates HCN and T-type channels

“…Results presented here are consistent with a recent report showing increased time in the awake stage of rats 2 days after i.p. administration of "coca paste" adulterated with caffeine (Schwarzkopf et al 2018). EEG recordings in rats have shown a decrease in the "power spectrum" of NREM sleep after a daily systemic (i.p.)…”

“…Cannabinoids, opiates, cocaine, amphetamine, methamphetamine, and "ecstasy" stand out among the most commonly abused drugs (Cadet and Bisagno 2013;Cadet et al 2014), which are combined with newly designed drugs (bath salts) whose deleterious effects are still far from being fully known (López-Rodriguez and Viveros 2019). In South America and especially in Argentina, the Oriental Republic of Uruguay and other South American countries, coca "paste" or "PACO" (which represents another inhalable form of cocaine besides crack) is massively consumed (Prieto et al 2016;Schwarzkopf et al 2018).…”

“…Caffeine effects on thalamocortical (ThCo) neurons have been described to involve altered calcium release and reuptake by the endoplasmic reticulum (Coulon et al 2009;Rankovic et al 2010), while inhibiting phosphodiesterase (Fontanez and Porter 2006;Rankovic et al 2010) and blocking adenosine receptors that play a central role on wake-sleep cycles (Lazarus et al 2011). Indeed, caffeine enhanced wakefulness-induced effects of cocaine in rodents when using coca "paste" samples during electroencephalographic recordings (Schwarzkopf et al 2018).…”

Neuropsychological functioning of individuals with coca paste use disorder

“…Coca paste is the non-refined by-product that is derived from the initial extraction process from coca leaves and serves as a substrate for the elaboration of cocaine hydrochloride. In contrast, crack is produced during a later process that uses cocaine hydrochloride (Pascale et al, 2014;Prieto et al, 2015;Schwarzkopf, Lagos, Falconi, Scorza, & Torterolo, 2018).…”

“…Coca paste is relatively easy to obtain illegally because of its lower cost compared to other substances, such as cocaine hydrochloride. As such, the consumption of coca paste is mostly concentrated in areas of low socio-economic status (Castaño, 2000;Fukushima et al, 2014;Galvalisi et al, 2015;Schwarzkopf et al, 2018), such as Latin American countries and especially Colombia, where it is one of the most frequently consumed illicit substances after marijuana and cocaine hydrochloride (ODC, 2017;UNODC, 2018). Today, there is no single standard formula, and consequently it is difficult to know the exact chemical composition of each product (Lopez-Hill et al, 2011;Meikle et al, 2013;Prieto et al, 2012;Sabogal-Carmona & Urrego-Novoa, 2012;Schwarzkopf et al, 2018).…”