Use of cognitive enhancers: methylphenidate and analogs

Stimulant and hallucinogenic novel psychoactive substances; an update

INTRODUCTION

The renewed interest in considering a range of stimulants, psychedelics and dissociatives as therapeutics emphasizes the need to draft an updated overview of these drugs' clinical and pharmacological issues.

AREAS COVERED

The focus here was on: stimulants (e.g. amphetamines, methamphetamine, and pseudoephedrine; phenethylamines; synthetic cathinones; benzofurans; piperazines; aminoindanes; aminorex derivatives; phenmetrazine derivatives; phenidates); classical (e.g. ergolines; tryptamines; psychedelic phenethylamines), and atypical (e.g. PCP/ketamine-like dissociatives) psychedelics.Stimulant and psychedelics are associated with: a) increased central DA levels (psychedelic phenethylamines, synthetic cathinones and stimulants); b) 5-HT receptor subtypes' activation (psychedelic phenethylamines; recent tryptamine and lysergamide derivatives); and c) antagonist activity at NMDA receptors, (phencyclidine-like dissociatives).

EXPERT OPINION

Clinicians should be regularly informed about the range of NPS and their medical, psychobiological and psychopathological risks both in the acute and long term. Future research should focus on an integrative model in which pro-drug websites' analyses are combined with advanced research approaches, including computational chemistry studies so that in vitro and in vivo preclinical studies of index novel psychoactives can be organized. The future of psychedelic research should focus on identifying robust study designs to convincingly assess the potential therapeutic benefits of psychedelics, molecules likely to present with limited dependence liability levels.

Rosmarinus officinalis and Methylphenidate Exposure Improves Cognition and Depression and Regulates Anxiety-Like Behavior in AlCl3-Induced Mouse Model of Alzheimer’s Disease

Alzheimer’s disease (AD) is a neurological illness that causes severe cognitive impairment. AD patients also experience at least one of the neuropsychiatric symptoms including apathy, depression, and anxiety during the course of their life. Acetylcholine esterase inhibitors are the available treatment options to alleviate cognitive deficits, whereas methylphenidate (MPH), a psychostimulant, is considered for the treatment of apathy in AD patients. Rosmarinus officinalis, a perennial herb, has been potentially known to have antioxidant and anti-inflammatory properties. The present study investigated the potential effects of MPH and R. officinalis in comparison with the standard drug, Donepezil, on cognition, anxiety, and depression in the AlCl₃-induced mouse model of AD. The animals were divided into eight groups (n = 8, each). The results revealed that the MPH- and R. officinalis-treated groups significantly improved memory impairment, whereas R. officinalis substantially reduced depression and anxiety as compared with other treatment groups. MPH treatment induced an antidepressant effect and increased anxiety-like behavior. Moreover, the AlCl₃ exposure led to the formation of amyloid beta (Aβ) plaques in mice hippocampus; however, none of the tested drugs caused a significant reduction in amyloid burden at the selected doses. The present study suggested the potential of R. officinalis to improve memory as well as neuropsychiatric symptoms in AD. Although R. officinalis improved cognitive abilities, it did not reduce the amyloid plaque burden, which indicates that the memory-enhancing effects of R. officinalis are due to some alternate mechanism that needs to be explored further.

Benefits and Harms of 'Smart Drugs' (Nootropics) in Healthy Individuals

'Smart drugs' (also known as 'nootropics' and 'cognitive enhancers' [CEs]) are being used by healthy subjects (i.e. students and workers) typically to improve memory, attention, learning, executive functions and vigilance, hence the reference to a 'pharmaceutical cognitive doping behaviour'. While the efficacy of known CEs in individuals with memory or learning deficits is well known, their effect on non-impaired brains is still to be fully assessed. This paper aims to provide an overview on the prevalence of use; putative neuroenhancement benefits and possible harms relating to the intake of the most popular CEs (e.g. amphetamine-type stimulants, methylphenidate, donepezil, selegiline, modafinil, piracetam, benzodiazepine inverse agonists, and unifiram analogues) in healthy individuals. CEs are generally perceived by the users as effective, with related enthusiastic anecdotal reports; however, their efficacy in healthy individuals is uncertain and any reported improvement temporary. Conversely, since most CEs are stimulants, the related modulation of central noradrenaline, glutamate, and dopamine levels may lead to cardiovascular, neurological and psychopathological complications. Furthermore, use of CEs can be associated with paradoxical short- and long-term cognitive decline; decreased potential for plastic learning; and addictive behaviour. Finally, the non-medical use of any potent psychotropic raises serious ethical and legal issues, with nootropics having the potential to become a major public health concern. Further studies investigating CE-associated social, psychological, and biological outcomes are urgently needed to allow firm conclusions to be drawn on the appropriateness of CE use in healthy individuals.

CRISPR-Cas and Its Wide-Ranging Applications: From Human Genome Editing to Environmental Implications, Technical Limitations, Hazards and Bioethical Issues

The CRISPR-Cas system is a powerful tool for in vivo editing the genome of most organisms, including man. During the years this technique has been applied in several fields, such as agriculture for crop upgrade and breeding including the creation of allergy-free foods, for eradicating pests, for the improvement of animal breeds, in the industry of bio-fuels and it can even be used as a basis for a cell-based recording apparatus. Possible applications in human health include the making of new medicines through the creation of genetically modified organisms, the treatment of viral infections, the control of pathogens, applications in clinical diagnostics and the cure of human genetic diseases, either caused by somatic (e.g., cancer) or inherited (mendelian disorders) mutations. One of the most divisive, possible uses of this system is the modification of human embryos, for the purpose of preventing or curing a human being before birth. However, the technology in this field is evolving faster than regulations and several concerns are raised by its enormous yet controversial potential. In this scenario, appropriate laws need to be issued and ethical guidelines must be developed, in order to properly assess advantages as well as risks of this approach. In this review, we summarize the potential of these genome editing techniques and their applications in human embryo treatment. We will analyze CRISPR-Cas limitations and the possible genome damage caused in the treated embryo. Finally, we will discuss how all this impacts the law, ethics and common sense.

The Use and Impact of Cognitive Enhancers among University Students: A Systematic Review

INTRODUCTION

Cognitive enhancers (CEs), also known as "smart drugs", "study aids" or "nootropics" are a cause of concern. Recent research studies investigated the use of CEs being taken as study aids by university students. This manuscript provides an overview of popular CEs, focusing on a range of drugs/substances (e.g., prescription CEs including amphetamine salt mixtures, methylphenidate, modafinil and piracetam; and non-prescription CEs including caffeine, cobalamin (vitamin B12), guarana, pyridoxine (vitamin B6) and vinpocetine) that have emerged as being misused. The diverted non-prescription use of these molecules and the related potential for dependence and/or addiction is being reported. It has been demonstrated that healthy students (i.e., those without any diagnosed mental disorders) are increasingly using drugs such as methylphenidate, a mixture of dextroamphetamine/amphetamine, and modafinil, for the purpose of increasing their alertness, concentration or memory.

AIM

To investigate the level of knowledge, perception and impact of the use of a range of CEs within Higher Education Institutions.

METHODOLOGY

A systematic review was conducted in adherence with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Whilst 1400 studies were identified within this study through a variety of electronic databases (e.g., 520 through PubMed, 490 through Science Direct and 390 through Scopus), 48 papers were deemed relevant and were included in this review.

RESULTS

The most popular molecules identified here included the stimulant CEs, e.g., methylphenidate, modafinil, amphetamine salt mixtures and caffeine-related compounds; stimulant CEs' intake was more prevalent among males than females; drugs were largely obtained from friends and family, as well as via the Internet. It is therefore suggested that CEs are increasingly being used among healthy individuals, mainly students without any diagnosed cognitive disorders, to increase their alertness, concentration, or memory, in the belief that these CEs will improve their performance during examinations or when studying. The impact of stimulant CEs may include tolerance, dependence and/or somatic (e.g., cardiovascular; neurological) complications.

DISCUSSION

The availability of CEs for non-medical indications in different countries is influenced by a range of factors including legal, social and ethical factors. Considering the risk factors and motivations that encourage university students to use CE drugs, it is essential to raise awareness about CE-related harms, counteract myths regarding "safe" CE use and address cognitive enhancement in an early stage during education as a preventative public health measure.

Prevalence of Stimulant, Hallucinogen, and Dissociative Substances Detected in Biological Samples of NPS-Intoxicated Patients in Italy

A number of new psychoactive substances (NPS) have been released in the last decade, and the list of NPS continues to grow. This paper reports a retrospective evaluation of the toxicological analyses in 1,445 suspected intoxication cases by psychostimulant, hallucinogen, and dissociative NPS occurring in hospitals across Italy from 2011 to 2019. The objectives of the study were to contribute to the monitoring of the NPS diffusion based on analytically confirmed intoxications, and to evaluate the importance of the clinical toxicological laboratory in the diagnosis of NPS intoxication. For at least one NPS of the considered classes, 246 patients (17.0%) tested positive. Forty-four different NPS were detected and a consistent turnover was observed during the nine-year period, especially regarding cathinones. Among the positive cases, 47.2% tested positive for dissociative NPS, with particular regard to ketamine. Hallucinogens (30.9%) was the second most frequent NPS involved. Stimulants were found in 20% of the positive cases with a considerable presence of cathinones. Findings confirm the dynamism of the NPS phenomenon, underline the importance of awareness of this new public health threat among health care professionals, and highlight the need for analytical confirmation for the identification of the drugs in forensic contexts.

Effects of Appearance- and Performance-Enhancing Drugs on Personality Traits

Appearance- and performance-enhancing drugs (APEDs) are commonly used by adolescents and young adults in an effort to improve not only athletic performance but also physical and mental efficiency and sexual appearance. The rationale for using these drugs is grounded in the perceived importance of external appearance, the quest for health and youth, and the urge to boost one's sexual performances. Although APED users tend to be quite moderate overall, some specific subpopulations can display pathological use associated with high-risk behaviors. A wide and diverse range of APEDs is now easily accessible to almost anyone through backdoor online avenues. Common APEDs include anabolic-androgenic steroids, non-steroidal anabolics, anorectics, diuretics and ergo/thermogenics, nootropics or "cognition enhancers," licit and illicit psychostimulants, and finally, sexual enhancers. The use of APEDs appears linked to several psychopathological disorders of unclear prevalence, e.g., body image disorders and eating disorders, perfectionism, but also depression and loneliness. The role of personality traits related to APED use has been investigated in adolescents and young adults, in elite and amateur athletes, and in chemsexers and associated with the above-reported personality traits. The studies herein analyzed show that APED consumption in the general population is quickly growing into a public health concern. It is therefore essential to launch prevention and intervention projects aimed at promoting safe instrumental use of the body, not only in sports disciplines but also among the general population, and to promote psychological aid procedures for people with substance use issues, depression and anxiety, and body image disorders.

Non-medical Use of Prescription Stimulants Among College Students: Non-oral Routes of Administration, Risk Factors, Motivations, and Pathways

Introduction: Non-medical use (NMU) of prescription stimulant medications is a continuing public health concern. Stimulant medications prescribed for attention-deficit/hyperactivity disorder (ADHD) are widely available on college campuses, and, as a consequence, college students may have multiple opportunities to engage in prescription stimulant NMU. This online self-report survey examined prescription stimulant NMU among college students, including: (1) patterns of non-oral route of administration (ROA); (2) motivations for non-oral ROAs; and (3) retrospectively recalled pathways of initiation. Method: The survey sample was created from a pool of 3,379 respondents, who were matched to a sampling frame constructed from the 18-26-year-old, college student sample of the 2016 American Community Survey (ACS). About 14% (n = 486) from the overall pool were identified as college students with self-reported prescription stimulant NMU, all of whom completed the survey. The survey covered user characteristics, prescription and illicit substance use, age of first NMU, motivations for NMU, sources of procurement, and ROAs used. Results: Among 486 students reporting prescription stimulant NMU, 43% had a lifetime diagnosis of ADHD. More than 90% reported polysubstance use, with 55% using illicit substances other than marijuana. Slightly more than 2 in 5 (43.3%) reported using illicit substances prior to prescription stimulant NMU, 24.6% used both at the same age, and 32.0% engaged in NMU of prescription stimulants prior to using illicit substances. Prescription stimulant NMU preceded prescription opioid NMU 45% of the time. More than a quarter of those engaged in prescription stimulant NMU (27.9%) initiated prescription stimulants alone or at the same age as other drugs. Most prescription stimulant NMU was oral, however 23.0% reported any non-oral use: snorting (20.4%), smoking (6.0%)and/or injection (3.5%). Non-oral use was associated with being male, obtaining medication from a dealer, use to get high, and/or a substance use disorder diagnosis. Conclusions: Prescription stimulant NMU often occurs in the larger context of other substance use among college students. Injection, an under-researched route for prescription stimulants, was associated with male gender, history of substance use and higher likelihood of illicit substance use. Nearly a quarter of college student survey respondents reported use with non-oral routes, which is associated with other high-risk behaviors. Efforts to reduce non-oral prescription stimulant NMU in college students are warranted.

New Psychoactive Substances: Evolution in the Exchange of Information and Innovative Legal Responses in the European Union

At the end of 2019, the European Monitoring Centre for Drugs and Drug Addiction was monitoring around 790 new psychoactive substances, more than twice the total number of controlled substances under the United Nations Conventions. These substances, which are not subject to international drug controls, include a wide range of molecules, including the assortment of drugs such as synthetic cannabinoids, stimulants, opiates, and benzodiazepines. Most of them are sold as "legal" substitutes for illicit drugs, while others are intended for small groups willing to experiment with them in order to know their possible new effects. At the national level, various measures have been taken to control new substances and many European countries have responded with specific legislation in favor of consumer safety and by extending or adapting existing drug laws to incorporate the new psychoactive substances. Moreover, since 1997, an early warning system has been created in Europe for identifying and responding quickly to the risks of new psychoactive substances. In order to establish a quicker and more effective system to address the criminal activities associated with new dangerous psychoactive substances, the European legal framework has considerably changed over the years.

The Psychonauts' World of Cognitive Enhancers

BACKGROUND

There is growing availability of novel psychoactive substances (NPS), including cognitive enhancers (CEs) which can be used in the treatment of certain mental health disorders. While treating cognitive deficit symptoms in neuropsychiatric or neurodegenerative disorders using CEs might have significant benefits for patients, the increasing recreational use of these substances by healthy individuals raises many clinical, medico-legal, and ethical issues. Moreover, it has become very challenging for clinicians to keep up-to-date with CEs currently available as comprehensive official lists do not exist.

METHODS

Using a web crawler (NPSfinder®), the present study aimed at assessing psychonaut fora/platforms to better understand the online situation regarding CEs. We compared NPSfinder® entries with those from the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and from the United Nations Office on Drugs and Crime (UNODC) NPS databases up to spring 2019. Any substance that was identified by NPSfinder® was considered a CE if it was either described as having nootropic abilities by psychonauts or if it was listed among the known CEs by Froestl and colleagues.

RESULTS

A total of 142 unique CEs were identified by NPSfinder®. They were divided into 10 categories, including plants/herbs/products (29%), prescribed drugs (17%), image and performance enhancing drugs (IPEDs) (15%), psychostimulants (15%), miscellaneous (8%), Phenethylamines (6%), GABAergic drugs (5%), cannabimimetic (4%), tryptamines derivatives (0.5%), and piperazine derivatives (0.5%). A total of 105 chemically different substances were uniquely identified by NPSfinder®. Only one CE was uniquely identified by the EMCDDA; no CE was uniquely identified by the UNODC.

CONCLUSIONS

These results show that NPSfinder® is helpful as part of an Early Warning System, which could update clinicians with the growing numbers and types of nootropics in the increasingly difficult-to-follow internet world. Improving clinicians' knowledge of NPS could promote more effective prevention and harm reduction measures in clinical settings.

Pharmacological Human Enhancement: An Overview of the Looming Bioethical and Regulatory Challenges

Cognitive enhancement, a rather broad-ranging principle, can be achieved in various ways: healthy eating and consistent physical exercise can lead to long-term improvements in many cognitive domains; commonplace stimulants such as caffeine, on the other hand, temporarily raise levels of alertness, attentiveness, and concentration; sedative substances are also used as an indirect form of enhancement to relax before an exam or an important meeting. Such approaches raise no ethical issue. Nonetheless, clinical research has led to the off-label use of drugs called nootropics or "smart drugs", which can, under certain conditions, elicit some degree of cognition-improving effects: methylphenidate and modafinil can enhance working memory and concentration in healthy individuals, although the significance and effectiveness of such applications are dubious. Such "cognitive enhancement" methods, however, do raise multiple ethical issues, and their contentious nature has caused bioethical authorities to lay out opinions and recommendations meant to regulate their use. Most notably, the Italian Committee on Bioethics has extensively dealt with the spread of nootropics, which resulted in the Italian Code of Medical Ethics including "cognitive enhancement" drugs and their prescription by doctors as critical points, along with cosmetic surgery (the latest version of the Code, updated in December 2017, deals with the two separately, in Article 76 and 76 BIS). The United States Presidential Commission for the Study of Bioethical Issues broadened the scope of cognitive enhancement techniques so as to include neural modifiers, i.e. mechanisms of brain and nervous system change: a much wider array of interventions, technologies, behaviors, and environmental conditions that may potentially affect several aspects of the human brain and nervous system. The potential of neuroscience to profoundly reshape society is nothing short of mind-blowing.

Neuroenhancement as Instrumental Drug Use: Putting the Debate in a Different Frame

The use of performance-enhancing drugs to study or work better is often called "cognitive enhancement" or "neuroenhancement" and sparked a debate between scholars from many disciplines. I argue that such behavior can better be subsumed under the more general category of "instrumental drug use". This broader perspective allows understanding neuroenhancement better from the perspective of addiction medicine and public health and supports a more consistent drug policy. I also summarize the most important systematic reviews and individual surveys of nonmedical substance use to study or work better. Different definitions and methodologies limit the comparability of these studies. The unified approach of drug instrumentalization would partially solve such problems. Finally, prevalence studies from the 1960s to 1980s as well as anecdotal evidence since the late 19th century show that instrumental drug use is and has been for a long time a common phenomenon. It should thus also be investigated and treated accordingly.