In psychiatric practice, stimulants are primarily used to treat disorders of attention and wakefulness, overlapping with the broader group of both traditional and recreationally used stimulants including caffeine, nicotine, mate, coca, khat, kratom as well as illicit derivatives such as methamphetamine and cocaine.

Stimulant medications have also been proposed as potential agents to meet some of the gaps where current psychiatric treatments fall short, for example in treatment-resistant depression, negative symptoms of schizophrenia, cognitive disorders such as dementia, as well as combating side effects of other psychotropics such as weight gain, sedation, and sexual dysfunction.

The risk of repurposing stimulants to fill unmet needs in psychiatry is twofold. Firstly, off-label prescribing with a lack of robust evidence, could be hazardous to patients who may not understand the experimental nature of the treatment. The risks may outweigh the benefits and the long-term consequences are not well understood, for example in relation to schizophrenia and cognitive degeneration. Secondly, there is a high risk of dependency. In for example treatment-resistant depression, the promise of stimulants improving apathy and providing symptom relief during the onset latency period for traditional antidepressants, needs to be carefully weighed against the high potential for dependency. This risk is compounded in vulnerable populations with comorbid psychiatric diagnoses, where up to 1 in 4 people with a serious mental illness have a comorbid substance use disorder.^142–144

There have long been concerns about stimulant prescribing for normal variations of human behavior and performance. One of the challenges here has been the overlay of social and cultural determinants of diseases, which is strongly the case in ADHD. It has been shown that there are cultural differences in parental sensitivities and social tolerance to externalizing behaviors.^145,146 Additionally, cultural bias within the existing diagnostic criteria has been cited as a contributing factor to geographic differences in ADHD diagnosis, further complicating the issue.¹⁴⁶

The risk with medicalizing behavior and performance is that non-pathological phenomena become labeled as diseases. This approach assumes a clear line between health and disorder, which is rarely the case in neuropsychiatry. There is also no cut point or bimodal distribution of attention, leading to arbitrariness in definition and hence the use of stimulants. Without specific biomarkers and relying on classifying disorders based on a constellation of symptoms, defining disease often depends on interpreting and identifying significant dysfunction and distress, which can be non-objective.¹⁴⁷

The rise of neurodivergence as an explanation for attention difficulties and underachievement reflects a broader trend where certain diagnoses gain and lose popularity over time, becoming widely accepted explanations for common challenges until another takes their place. While neurodivergence offers a valuable framework, it can also lead to overgeneralizations, diagnostic overshadowing, and the misinterpretation of normal life struggles as clinical disorders. This may result in the inappropriate use of medications as a quick fix in place of therapy or lifestyle changes, particularly when these conditions are heavily publicized or culturally endorsed.

An additional concern is the medicalization of social issues leading to overprescribing. A number of contemporary factors affect diagnosis in this arena. In the case of childhood ADHD, social pressures to behavioral conformity, school governance, and media marketing are all contributors.¹⁴⁷ Local school funding is increasingly incentivized or influenced by student academic performance. Examples here include the 2001 No Child Left Behind Act in the US and the National Assessment Program – Literacy and Numeracy in Australia. Allocation of additional school or university support is often financed or resourced depending on a diagnosis. In time-constrained, resource-limited nuclear families, and underfunded educational systems, where academic pressures are intense, there is often a shrinking tolerance for behaviors that do not align with expectations, especially in the context of an attention economy. Prescribers may face pressure to make quick decisions and weigh in on resource allocation, often with limited information and there is the risk that medication might be prescribed to address parental distress rather than a child’s actual needs. Like with other neurodevelopmental disorders, ADHD has been proposed as a disorder spectrum or continuum, also conferring a risk of diagnostic overreach.

The use of stimulants for ADHD is also unique in another domain. In no other branch of psychiatry does misdiagnosis and prescription of inappropriate medications become self-reinforcing. However, stimulants are largely pleasurable for most users and enhance mood, attention, focus, and energy. Consequently, many people prescribed these agents will perceive some subjective benefit regardless of whether they do or do not have ADHD and uniquely prescription tends to reinforce the diagnosis whether correct or not.

Neuroenhancement, the use of treatment to improve cognitive, emotional, or behavioral functioning beyond what is considered the realms of disease states, is hotly debated and highlights the issue of treatment boundaries. Sakakibara et al. (2020) argue that it is essential to recognize the ambiguities in treatment, where the coexistence of multiple meanings blurs the boundaries between therapeutic intervention and enhancement.¹⁴⁸ This is particularly relevant in psychiatry, where psychotropic medications not only manage symptoms of mental illness but also alter human experiences, emotions, and perceptions. For instance, subjective displeasure due to emotional blunting and anxiety was a key factor for antidepressant discontinuation in a third of 896 surveyed study participants.¹⁴⁹ Sakakibara et al. (2020) go on to argue that neuromodifiers lie on a continuum between treatment and enhancement and overlap with the elements of prevention, pain relief, and pleasure-seeking. This raises ethical questions about the appropriate limits of medical intervention and the potential societal implications of enhancing human capacities beyond their original state. It challenges the distinction between healing and enhancement and prompts a reexamination of what it means to treat versus augment.

Perhaps some of the difficulty in defining treatment in psychiatry arises from its inherent tension, as the field often seeks to reduce the rich complexities of embodied human experience to mental processes. This reductionist approach risks overshadowing the nuanced interplay between mind and body, potentially missing key aspects of human suffering. It raises the question of whether psychiatric clinicians are tasked solely with the medicine of the mind, or if they should also serve as advocates for ethical and humane treatment of the broader human experience, including physical and existential dimensions of suffering.

The argument by Sakakibara et al. (2020) on the continuum of treatment with pleasure-seeking is particularly intriguing, raising the distinction between hedonia and eudaimonia, or immediate pleasure versus self-actualization and fulfillment regardless of circumstances. Psychotherapy is another domain that crosses into these territories in addressing both ease and disease.

One salient point raised by many is the lack of evidence to support that prescribed stimulants such as amphetamine and methylphenidate can fulfill a promise of neuroenhancement.^150–153 The findings of the metanalysis of dementia medications in healthy individuals are even more disappointing, showing no improvement in attention, vigilance, concentration, or memory.^154,155 Some have argued that optimal function in one domain may mean a trade-off in another.¹⁵³ A meta-analysis of 148 studies found methylphenidate improved academic productivity but not accuracy, while others found improved attention and vigilance may be at the cost of long-term memory, executive functions, and creative thinking.^156,157 Others pose that the presumption that stimulants improve cognition is misguided and that more research should focus on the volitional advantage they provide. They are known to treat apathy, improve task enjoyment, and make users more inclined to engage in high-effort, high-reward tasks.¹⁵¹ These debates aside, disease treatment should lead the way in terms of resource allocation for medical research and community health initiatives, ensuring that the focus remains on addressing genuine needs over enhancement potentials.