Misuse and abuse of pregabalin and gabapentin: cause for concern?

Gabapentinoids (e.g. pregabalin and gabapentin) are widely used in neurology, psychiatry and primary healthcare but are increasingly being reported as possessing a potential for misuse. In fact, increasing levels of both prescriptions and related fatalities, together with an anecdotally growing black market, have been reported from a range of countries. This article reviews the current evidence base of this potential, in an attempt to answer the question of whether there is cause for concern about these drugs. Potent binding of pregabalin/gabapentin at the calcium channel results in a reduction in the release of excitatory molecules. Furthermore, gabapentinoids are thought to possess GABA-mimetic properties whilst possibly presenting with direct/indirect effects on the dopaminergic 'reward' system. Overall, pregabalin is characterized by higher potency, quicker absorption rates and greater bioavailability levels than gabapentin. Although at therapeutic dosages gabapentinoids may present with low addictive liability levels, misusers' perceptions for these molecules to constitute a valid substitute for most common illicit drugs may be a reason of concern. Gabapentinoid experimenters are profiled here as individuals with a history of recreational polydrug misuse, who self-administer with dosages clearly in excess (e.g. up to 3-20 times) of those that are clinically advisable. Physicians considering prescribing gabapentinoids for neurological/psychiatric disorders should carefully evaluate a possible previous history of drug abuse, whilst being able to promptly identify signs of pregabalin/gabapentin misuse and provide possible assistance in tapering off the medication.