Nootropics smart drugs and cognitive enhancers.
They are drugs, supplements, and other substances that claim to improve cognitive function, particularly executive functions, attention, memory, creativity, or motivation: Salts of Amphetamine class, methylphenidate pills.
A true nootropic must fulfill Giurgea’s five criteria for the category:
Improves working memory and learning.
Supports brain function under hypoxic conditions or after electroconvulsive therapy.
Protection of the brain from physical or chemical toxicity.
Natural cognitive functions are enhanced.
Non-toxic to humans, without depression or stimulation of the brain.
Nootropics are frequently advertised with unproven claims of effectiveness at improving cognition.
Prescriptions of nootropics for healthy people, are discouraged on the basis that the cognitive effects appear to be highly variable among individuals, are dose-dependent, and limited or modest at best.
The use of prescription stimulants is especially prevalent among students.
5–35% of college students report using diverted ADHD stimulants, which are primarily used for enhancement of academic performance rather than as recreational drugs.
Long-term safety evidence is typically unavailable for nootropics.
There is little evidence that they enhance cognition in people having no cognitive impairments.
Systematic reviews and meta-analyses using low doses of certain central nervous system stimulants found that these drugs enhance cognition in healthy people.
Stimulants that demonstrate cognition-enhancing effects in humans act as direct agonists or indirect agonists of dopamine receptor D1, adrenoceptor A2, or both types of receptor in the prefrontal cortex.
Relatively high doses of stimulants cause cognitive deficits.
Amphetamine at low-dose improves cognitive functions: inhibitory control, episodic memory, working memory, and aspects of attention in healthy people and in individuals with ADHD.
Low doses of amphetamine improve memory consolidation, in turn leading to improved recall of information in non-ADHD youth.
Low doses of amphetamine improves
motivation to perform tasks and performance on tedious tasks that required a high degree of effort.
Methylphenidate is a benzylpiperidine derivative that improves working memory, episodic memory, and inhibitory control, aspects of attention, and planning latency in healthy people.
Methylphenidate may improve task saliency and performance on tedious tasks.
At above optimal doses, methylphenidate it decrease learning.
The eugeroics, armodafinil and modafinil, are classified as wakefulness-promoting agents.
Modafinil increases alertness, particularly in sleep-deprived individuals, and facilitates reasoning and problem solving in non-ADHD youth.
Modafinil intake enhances executive function.
Modafinil may not produce improvements in mood or motivation in sleep deprived or non-sleep deprived individuals.
Caffeine in a meta-analysis is found to increase in alertness and attentional performance.
Nicotine in meta-analyses of 41 clinical studies concluded that nicotine administration or smoking improves alerting and orienting attention and episodic and working memory and slightly improves fine motor performance.
Racetams, such as piracetam, oxiracetam, phenylpiracetam, and aniracetam, are often marketed as cognitive enhancers and sold over the counter, are often referred to as nootropics, but this property is not well established.
According to the US Food and Drug Administration, Piracetam, a racetam, is not a vitamin, mineral, amino acid, herb or other botanical, or dietary substance for use by humans to supplement the diet by increasing the total dietary intake.
It is not a concentrate, metabolite, constituent, extract or combination of any such dietary ingredient, and are not foods and they are not intended to affect the structure or any function of body, and they are not generally recognized as safe and effective for use under the conditions prescribed, recommended, or suggested in their labeling.
Nootropic substances include the cholinergics, compounds and analogues of choline.
Choline is an essential nutrient needed for the synthesis of acetylcholine, and phosphatidylcholine, which is a structural component of brain cell membranes.
Citicoline consists of choline and cytidine.
Citicoline is likely effective for improving memory and learning in older people with mild cognitive decline, as well as in people who are recovering from a stroke, but there is little evidence it enhances cognition in young, healthy people.
Tolcapone improves verbal episodic memory and episodic memory encoding.
Levodopa improves verbal episodic memory and episodic memory encoding.
Atomoxetine may improve working memory and attention.
Desipramine may improve working memory and attention, including concentration, psychomotor performance, attention, reaction times, and other indicators of brain function.