What Are the Best Nootropics? The Top 7 Powerful Nootropics

“Smart drugs,” often referred to as nootropics, are synthetic compounds or natural substances (i.e. plant extracts) that have been shown in studies to improve overall mental performance and well-being.

Nootropics have become a hot topic, and are in high demand, due to an increasingly competitive society wherein many people choose to research and experiment with these compounds, often referred to as “brain hacking” or “biohacking.” The primary nootropic effects that people are interested in are improved memory, improved creativity, improved concentration, motivation, and focus, better sleep, and an overall increase in well-being and positive mood. Based on reviews and reports, many people seem to be on a quest to find the best nootropics stack (combination), if they choose to consume these substances.

In this nootropic review, we’ll discuss some of the most popular and powerful nootropic compounds, how they work, and a summary of available research and anecdotal evidence to support the nootropic benefits as well as side effects.

Disclaimer: ELV Bioscience (www.elvbio.com) does not make any recommendations for use, inclusive of the following compounds in this review of popular and potent compounds with nootropic effects.  


Caffeine Chemical Structure

Caffeine is the most widely used psychoactive substance in the world. Caffeine is an alkaloid most often consumed in the form of coffee, tea, guarana, chocolate, and kola nuts. However, caffeine is also consumed in supplemental form, whether it is extracted and isolated from a natural source, such as pure caffeine isolate (from green tea) by ELV Bioscience, or whether it is made synthetically. Many popular supplemental sources of caffeine include pre-workout products, energy drinks, and energy shots. Caffeine is a central nervous system stimulant in the methylxanthine class of compounds.

How Caffeine Works?

Caffeine is a central nervous system stimulant, which works by way of blocking (antagonizing) adenosine receptors in the brain, causing a sense of alertness. Adenosine is a naturally occurring molecule that accumulates throughout the day to help slow down neurotransmission, promote a sense of calm and tiredness, and aid in supporting the natural circadian rhythm.

Caffeine Benefits:

Research has shown that caffeine consumption, within a recommended dose range, can have several benefits. Studies have shown that the benefits of caffeine can include possible protection against Alzheimer’s disease and dementia, improved exercise output and performance, and improved erectile function in men. Based on available research

Caffeine Side Effects:

Common side effects of excess caffeine consumption can include feeling jittery or anxious as well as difficulty sleeping due to caffeine’s long half-life of 5-6 hours. Other side effects of excessive caffeine consumption can include elevated heart rate and blood pressure due to vasoconstriction. Common side effects of caffeine withdrawal from prolonged consumption can include fatigue, malaise, and headache.

Caffeine Dosage:

Several health authorities, including the Mayo Clinic, Harvard, and the American Heart Association, suggest that consuming up to 400mg of caffeine per day in healthy adults is considered safe.



L-Theanine is a non-essential amino acid that naturally occurs in the select tea plants. The most popular natural source of theanine is Camellia Sinensis, which is a plant from which white, green, and black teas are made. Guayusa is another plant that contains theanine.   Theanine is also consumed in supplement form as well, whether it is naturally isolated from a tea plant, or whether it is synthetically produced. Theanine is one of the best nootropics, which has become very popular in recent years. This Theanine review will focus on L-Theanine, which is the naturally occurring enantiomer. D-Theanine is the opposite enantiomer but does not have as much research supporting its safety and efficacy.

How Theanine Works?

L-Theanine natural nootropic that is a structural analogue of two other naturally occurring amino acids, L-Glutamine, and L-Glutamate. Theanine is the primary contributor to “umami” (savory) flavor notes found in green tea.

Theanine is water-soluble, absorbs through the small intestine, and passes through the blood-brain barrier intact. One in the brain (central nervous system) Theanine binds to glutamate receptors since as we discussed earlier, it is structurally similar to the amino acid neurotransmitter – glutamate. Glutamate is an excitatory (stimulating) neurotransmitter. Since Theanine binds to glutamate receptors, specifically AMPA and kainate receptors, and the NMDA receptor, it can block some of the excitatory effects of glutamate. Theanine also blocks the reuptake of glutamine and glutamate by blocking their respective transporters. This is why many people who consume Theanine, whether in smaller amounts from tea or in larger amounts from supplements, often report that it promotes a sense of calm.

Theanine has been shown to increase levels of dopamine, GABA, glycine and serotonin levels in certain areas of the brain. Currently, the available research is not fully clear on Theanine’s effect on serotonin given that some research shows an increase and other research shows a decrease in serotonin concentrations. Theanine has also been shown to increase levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in various studies. L-Theanine has a half-life of approximately 3-4 hours following oral administration.

Theanine Benefits:

Theanine is often reported to promote a sense of calm, anxiety/stress relief, improved mood, improved focus, and the ability to create synergy with caffeine by reducing caffeine side effects. Research shows that Theanine may be able to inhibit glutamate excitotoxicity. Theanine also possesses antioxidant properties, which can promote both the central nervous system and systemic benefits.

Theanine Side Effects:

While Theanine is considered safe by many regulatory authorities including the US FDA, some people do report side effects. Some common side effects may include fatigue, “brain fog,” or in more rare cases, a paradoxical effect wherein Theanine can promote an anxious state.

Theanine Dosage:

A research organization named Natural Standard has suggested that Theanine is safe up to 1,200mg per day. The most common supplemental dosages are 100mg-200mg. Theanine content in tea can range from approximately 8mg to approximately 50mg in shade-grown teas such as Matcha green tea.



Phenibut, originally developed in the Soviet Union in the 1960’s, is a GABA (γ-aminobutyric acid) analogue, which consists of the naturally occurring endogenous amino acid neurotransmitter GABA, with a phenyl group. This allows phenibut to cross the blood brain barrier, whereas GABA supplementation cannot. Phenibut is classified as a central nervous system depressant, but uniquely, it promotes both anxiolytic effects and stimulant effects. Lower concentrations of phenibut are responsible for the stimulant effects, by causing a release of dopamine. In higher concentrations, phenibut acts as more of a sedative. Phenibut, such as phenibut from ELV Bioscience, is in HCL salt form. This is the form that has been most widely studied. There are other forms of phenibut such as free amino acid (Phenibut FAA) and 4-Fluorophenibut (F-Phenibut) but these forms have not been as well studied or used.

How Phenibut Works?

Phenibut has been shown to bind to and activate GABA-b receptors in the brain, similar to the way baclofen works. In very high concentrations, phenibut has also shown to bind to GABA-a receptor, which are the same receptors that benzodiazepines and alcohol (ethanol) bind to. Phenibut research has also shown that it blocks α2δ subunit-containing voltage-gated calcium channels which is why phenibut effects are different from baclofen, for example. Phenibut research has shown that it has a half-life of approximately 5 hours, with an onset time following oral administration of approximately 2-3 hours.  

Phenibut Benefits:

Phenibut has been shown to be effective in reducing anxiety and stress, without sedation, at low to moderate doses. In higher doses, phenibut has been shown to relieve insomnia. Other available research and phenibut reviews report that it can be effective for mitigating feelings of depression, and subsequently, for promoting a sense of well-being.

Phenibut Side Effects:

Common phenibut side effects, typically when used in excess, can include agitation, anxiety, headache, hangover, and nausea.



Tianeptine, often in the form of tianeptine sodium such as the ELV Bioscience Tianeptine product, is classified as a Selective Serotonin Reuptake Enhancer. However, tianeptine possesses activity at other receptors in the brain which contributes to the overall effects of tianeptine. Research has shown that tianeptine has anti-depressant and anxiolytic properties. Although tianeptine has shown to have anxiolytic effects, it has not shown to have anticholinergic or sedative properties, nor has tianeptine been linked to cardiovascular side effects.

How Tianeptine Works?

As Selective Serotonin Reuptake Enhancer, tianeptine is a positive allosteric modulator of SERT (serotonin transporter), but unlike similar compounds with this action, tianeptine appears to enhance the reuptake of serotonin, rather than inhibit it like tricyclic anti-depressants do. Further tianeptine research to determine its mechanism of action has shown that it is unlikely that tianeptine’s primary mechanism of action is from modulating serotonin levels. Tianeptine has been shown to be a full agonist of the mu-opioid receptor, and to a much lesser extent, a full agonist of the delta-opioid receptor. It is believed that this is the primary mechanism of action whereby tianeptine has shown to possess anti-depressant effects. Unlike traditional opioid receptor agonists, available research has not shown tianeptine to result in tolerance or withdrawal. Tianeptine is also active at the AMPA and NMDA receptors, which blocks some of the effects of glutamate. This effect has shown to create a release in BDNF. Despite tianeptine’s classification as a Selective Serotonin Reuptake Inhibitor, research has shown tianeptine to increase dopamine release. Research has shown tianeptine to be highly bioavailable upon oral administration, with a half-life of approximately 3 hours. Tianeptine is primarily metabolized in the liver.

Tianeptine Benefits:

Although tianeptine has a complex and not fully understood mechanism of action, research and tianeptine reviews have suggested that it has many benefits, including anxiety and stress relief, improvements in mood and sense of well-being, as well as potential pain-relieving and anticonvulsant effects. By increasing BDNF, tianeptine has been shown in animal research to potentially protect against stress-related neurochemical and neuronal changes in the brain.

Tianeptine Side Effects:

Common side effects of tianeptine have been shown to include nausea, headache, dizziness, drowsiness, constipation, and dry mouth.  

DMAA (1,3-dimethylamylamine):


DMAA, also known as methylhexanamine, dimethylamine, and 1,3-DMAA is a sympathetic nervous system stimulant, originally intended as a nasal decongestant. It is available from ELV Bioscience in powder or liquid form. DMAA has been tremendously popular as an energy-boosting supplement, with reported appetite suppressing and mood-enhancing properties. DMAA reviews often suggest that it is used in conjunction with caffeine to enhance its stimulatory and thermogenic effects. DMAA was sold as a dietary supplement in many weight loss and energy products, and some products still contain DMAA, despite the FDA warning against its use in dietary supplements. Many of these supplement companies claim that DMAA could be naturally found in the oil of the geranium plant, but very little, if any, evidence exists to show this to be true. 

How DMAA Works?

DMAA stimulates the sympathetic nervous system, much like ephedrine and adrenaline, causing vasoconstriction and bronchodilation. Research has shown that following oral administration, DMAA has a half-life of approximately 8.5 hours.

DMAA Benefits:

Reviews and reports on DMAA use suggest that some find its benefits to include increased physical performance and endurance, increased energy, appetite suppression, thermogenesis and lipolysis (fat loss), as well as improved mood and focus.

DMAA Side Effects:

Reports of DMAA side effects include increased blood pressure, increased heart rate, anxiety, irritability, and a crash following use. DMAA in excessive doses has been shown the potential to create adverse cardiovascular events.

DMHA (Octodrine):


DMHA is often referred to as, 2-Amino-6-methyl heptane, 6-Methyl-2-heptylamine, 2-Aminoisoheptane, and 1, 5-Dimethylhexylamine. DMHA is available from ELV Bioscience in powder and liquid form.

How DMHA Works?

DMHA is a stimulant with a similar chemical structure to DMAA. DMHA has become popular in dietary supplements as a replacement for DMAA. DMHA has a half-life of approximately 9 hours.

DMHA Benefits:

There is little research available on DMHA, but DMHA reviews and reports suggest that it has similar effects to DMAA, but it is less potent on a milligram per milligram basis. These reviews and reports suggest DMHA is often used for performance enhancement, energy, weight loss, and improvements in mood and focus.

DMHA Side Effects:

Due to DMHA’s similarity to DMAA, similar side effects have been reported, such as increased heart rate, blood pressure, and vasoconstriction. Very little research currently exists on DMHA.



Nicotine is the principal alkaloid in the tobacco plant, which belongs to the nightshade family, which also includes potatoes, tomatoes, and eggplants. Although a subject of much controversy, many people report that nicotine provides nootropic benefits. Of course, the nootropic community’s interest in nicotine is related to routes of administration other than smoking, such as lozenges and gum. Nicotine has been used for centuries as a natural stimulant by way of cultures around the world. Before the appearance of cigarettes and cigars, human beings used to bite on tobacco leaves. While more research is needed, existing research does not draw significant correlations between nicotine itself and cancer. Smoking on the other hand is the primary contributor of carcinogens.

How Nicotine Works?

Some available research, in addition to anecdotal reports, suggests that nicotine can promote working memory improvement, alertness, and improvements in mood and concentration. Nicotine binds to nicotinic acetylcholine receptors in the brain, which promotes the release of certain neurotransmitters, such as dopamine. This effect is often why nicotine is considered to be quite addictive. Nicotine has also shown to increase levels of endogenous opioids in the brain (endorphins). Nicotine has a half-life of approximately two hours and is metabolized in the liver by cytochrome P450 enzymes.


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