Theanine

From PsychonautWiki
(Redirected from L-Theanine)
Jump to: navigation, search
Yellow-warning-sign1.svg

This page has not been approved by the PsychonautWiki administrators.

It may potentially contain incorrect information, particularly regarding that of dosage, duration, subjective effects, toxicity and other risks.

Summary sheet: Theanine
Theanine
Molecular structure of Theanine
L-Theanine.svg
Chemical Nomenclature
Common names Theanine, L-Theanine, L-γ-glutamylethylamide and N5-ethyl-L-glutamine
Systematic name N-ethyl-L-glutamine; (2S)-2-ammonio-5-(ethylamino)-5-oxopentanoate
Class Membership
Psychoactive class Nootropic
Chemical class Amino acid analogue
Routes of Administration

WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.



Oral
Dosage
Threshold 50 - 75 mg
Light 75 - 175 mg
Common 175 - 300 mg
Strong 300 - 500 mg
Heavy 500 mg +
Duration
Total 3 - 6 hours[1]
Onset 30 - 90 minutes[2]
Peak 1 - 3 hours
After effects 6 - 12 hours









DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.

Theanine (also known as L-Theanine, L-γ-glutamylethylamide and N5-ethyl-L-glutamine) is an analog of the amino acids of glutamate and glutamine. It was discovered as a constituent of green tea in 1949 and in 1950 was isolated from gyokuro leaves, which have high theanine content.[3]

The appearance of the name "theanine" without a prefix is understood to imply the L-enantiomer, which is the form found in fresh teas and in some, but not all dietary supplements. The opposite D-enantiomer has far less studied pharmacologic properties, but is present in racemic chemical preparations, and substantially in some studied theanine supplements.

This compound is used as a nootropic for its calming and relaxing properties. It is often taken in combination with caffeine as it has been shown to mitigate its negative aspects, such as anxiety, increased blood pressure and diminished sleep quality, while possibly improving upon the positive aspects.[4][5][6][7] Its ability to enhance attention has been repeatedly verified.[8][9][10][11][12][13][14]

A recent systematic review of the effects of theanine and caffeine has confirmed that the combination seems to improve aspects of attention.[15] The combination of L-theanine and caffeine may improve attention more than caffeine alone.[16][17]

Chemistry

Theanine, or N-ethyl-L-glutamine, is an amino acid analogue of L-glutamine. Its structure is comprised of a five carbon straight chain carboxylic acid called pentanoic acid, which is bonded to an amino group at R2, and an additional ketone group at R5. Also substituted at R5 of the pentanoic group is an ethylamino chain connected at its amino constituent. Theanine is understood to refer to the levorotary enantiomer, which is well documented, rather than the relatively unresearched dextrorotary enantiomer.

Pharmacology

Theanine is structurally similar to the excitatory neurotransmitter glutamate, and in accordance, binds to glutamate receptors, though with much lower affinity in comparison. Specifically, it binds to ionotropic glutamate receptors including the AMPA and kainate receptors and, to a lesser extent, the NMDA receptor.[18][19][20][21] It acts as an antagonist of the former two sites[22] and as an agonist of the latter site.[23] In addition, it inhibits glutamine transporters and glutamate transporters, and thus acts as reuptake inhibitor of glutamine and glutamate.[24][25][26]

Theanine increases dopamine, GABA, and glycine levels in various areas of the brain.[27][28][29][30] It also affects serotonin in a manner which is still a matter of debate in the scientific community, with separate studies showing increases and decreases in brain serotonin levels using similar experimental protocols.[31][32]

These various changes in neurotransmitter levels contribute to the calming and nootropic properties of theanine.

Subjective effects

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. The listed effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances and are more likely to induce a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include injury or death.

Physical effects
Child.svg

Cognitive effects
User.svg


Toxicity and harm potential

Theanine is non-addictive, is not known to cause brain damage, and has an extremely low toxicity relative to dose. Similar to many other nootropics drugs, there are relatively few physical side effects associated with acute theanine exposure. Various studies have shown that in reasonable doses in a careful context, it presents no negative cognitive, psychiatric or toxic physical consequences of any sort.

It is strongly recommended that one use harm reduction practices when using this drug.

Tolerance and addiction potential

Theanine is not habit-forming and the desire to use it can actually decrease with use. It is most often self-regulating.

Tolerance to the effects of theanine are built up after prolonged and repeated usage. After that, it takes about 5 days for the tolerance to be reduced to half and 10 days to be back at baseline (in the absence of further consumption). Theanine presents cross-tolerance with no other known compounds, meaning that after the consumption of theanine all other psychoactive compounds will not have a reduced effect.

Legality

Handcuffs-300px.png

This legality section is a stub.

As such, it may contain incomplete or wrong information. You can help by expanding it.

Theanine is freely available to possess and distribute and is approved in most countries as a dietary supplement.

See also

External links

References

  1. Kinetics of L-Theanine Uptake and Metabolism in Healthy Participants Are Comparable after Ingestion of L-Theanine via Capsules and Green Tea | http://jn.nutrition.org/content/142/12/2091
  2. Kinetics of L-Theanine Uptake and Metabolism in Healthy Participants Are Comparable after Ingestion of L-Theanine via Capsules and Green Tea | http://jn.nutrition.org/content/142/12/2091
  3. Components of Gyokuro | http://www.ippodo-tea.co.jp/en/tea/gyokuro_02.html
  4. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/22214254
  5. The acute effects of L-theanine in comparison with alprazolam on anticipatory anxiety in humans (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/15378679
  6. L-Theanine reduces psychological and physiological stress responses (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/16930802
  7. Acute effects of theanine, caffeine and theanine-caffeine combination on attention | www.ncbi.nlm.nih.gov/pubmed/26869148
  8. The combined effects of L-theanine and caffeine on cognitive performance and mood (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/18681988
  9. The effects of L-theanine, caffeine and their combination on cognition and mood (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/18006208
  10. L-theanine and caffeine improve task switching but not intersensory attention or subjective alertness (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/20079786
  11. L-theanine and caffeine in combination affect human cognition as evidenced by oscillatory alpha-band activity and attention task performance (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/18641209
  12. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/21040626
  13. Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention task (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/22326943
  14. Acute effects of theanine, caffeine and theanine-caffeine combination on attention (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/26869148
  15. Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a systematic review and meta-analysis | www.ncbi.nlm.nih.gov/pubmed/24946991
  16. The combined effects of L-theanine and caffeine on cognitive performance and mood (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/18681988
  17. The effects of L-theanine, caffeine and their combination on cognition and mood (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/18006208
  18. The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/17182482
  19. Inhibition by theanine of binding of [3H]AMPA, [3H]kainate, and [3H]MDL 105,519 to glutamate receptors (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/12596867
  20. Neuroprotective effects of theanine and its preventive effects on cognitive dysfunction (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/21477654
  21. Neuroprotective effects of the green tea components theanine and catechins (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/12499631
  22. Neuroprotective effects of the green tea components theanine and catechins (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/12499631
  23. Behavioral and molecular evidence for psychotropic effects in L-theanine (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/21861094
  24. Neuroprotective effects of the green tea components theanine and catechins (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/12499631
  25. Inhibition of glutamate transporter by theanine enhances the therapeutic efficacy of doxorubicin (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/11325559
  26. Theanine and glutamate transporter inhibitors enhance the antitumor efficacy of chemotherapeutic agents (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/14643924
  27. The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/17182482
  28. Behavioral and molecular evidence for psychotropic effects in L-theanine (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/21861094
  29. Theanine, r-glutamylethylamide, increases neurotransmission concentrations and neurotrophin mRNA levels in the brain during lactation (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/17904164
  30. Effect of theanine, r-glutamylethylamide, on brain monoamines and striatal dopamine release in conscious rats (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/9566605
  31. Effect of theanine, r-glutamylethylamide, on brain monoamines and striatal dopamine release in conscious rats (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/9566605
  32. Theanine-induced reduction of brain serotonin concentration in rats (PubMed.gov / NCBI) | https://www.ncbi.nlm.nih.gov/pubmed/9614715
  33. A combination of green tea extract and l-theanine improves memory and attention in subjects with mild cognitive impairment: a double-blind placebo-controlled study. (PubMed.gov / NCBI) | http://www.ncbi.nlm.nih.gov/pubmed/21303262