Developments in neuroscience have raised the possibility that pharmaceuticals may be used to enhance memory, mood, and attention in people who do not have an illness or disorder, a practice known as “cognitive enhancement.” We describe historical experiences with two medicinal drugs for which similar enhancement claims were made, cocaine in the late 19th and early 20th centuries, and amphetamines in the mid 20th century. These drugs were initially introduced as medicinal agents in Europe and North America before becoming more (...) widely used for a variety of purposes, including what would nowadays be considered cognitive enhancement. Their trajectory of use conformed to the typical use cycle of psychotropic drugs. There was an initial steep rise in prescribing for medical use, followed by expanded nonmedical use that was fueled by enthusiasm for the drugs’ effects. As the number of regular users increased, problems related to use (such as addiction) became apparent, societal concern increased, and laws were passed banning nonmedical use and eventually, medical use. This historical experience draws attention to the adverse side effects of enhancement use that only become apparent with regular, wide-scale use of a drug. We highlight the similarities between the enthusiasms for cocaine and amphetamines and the current enthusiasms for using prescription stimulants for cognitive enhancement. We argue bioethicists should not encourage the cognitive enhancement use of drugs such as methylphenidate in the absence of evidence on the efficacy and safety of their use for cognitive enhancement purposes. (shrink)

There is growing evidence that dopamine replacement therapy (DRT) used to treat Parkinson’s Disease can cause compulsive behaviours and impulse control disorders (ICDs), such as pathological gambling, compulsive buying and hypersexuality. Like more familiar drug-based forms of addiction, these iatrogenic disorders can cause significant harm and distress for sufferers and their families. In some cases, people treated with DRT have lost their homes and businesses, or have been prosecuted for criminal sexual behaviours. In this article we first examine the evidence (...) that these disorders are caused by DRT. If it is accepted that DRT cause compulsive or addictive behaviours in a significant minority of individuals, then the following ethical and clinical questions arise: Under what circumstances is it ethical to prescribe a medication that may induce harmful compulsive behaviours? Are individuals treated with DRT morally responsible and hence culpable for harmful or criminal behaviour related to their medication? We conclude with some observations of the relevance of DRT-induced ICDs for our understanding of addiction and identify some promising directions for future research and ethical analysis. (shrink)