L-Theanine

Theanine · gamma-glutamylethylamide · L-Theanine

Mechanism

L-theanine (gamma-glutamylethylamide) is a non-proteinogenic amino acid occurring mainly in green tea (Camellia sinensis). Human and rodent studies describe a promotion of relaxed wakefulness and anxiolytic effects, mediated by modulation of glutamate receptors, an increase in GABA and effects on alpha brain waves. Controlled efficacy and PK data in the horse are largely lacking. Compliance-relevant: the FEI has explicitly named theanine as one of the calming-active, GABA-agonistic amino acids of interest in calming agents. The FEI status must therefore be checked before competition; a conservative classification as Controlled Medication is indicated.

Cautions

· Horse-specific efficacy/PK data lacking
· FEI has named theanine as a calming-active/GABA-agonistic amino acid — check status before competition
· Often only in combination products — mind the overall formulation

Sources

PMID:18296328Nobre et al. 2008 (Asia Pac J Clin Nutr) — L-Theanin und mentaler Zustand (human)

PMID:16930802Kimura et al. 2007 (Biol Psychol) — L-Theanin reduziert Stressreaktionen (human)

FEI EPSL 2024FEI Equine Prohibited Substances List 2024 — calming amino acids

Equiterna Score

58/100

solid

Science4.5/10

Practical experience6/10

Safety7.2/10

Overall score scale

high overall75–100solid55–74limited0–54

How the Equiterna Score is built

The Equiterna Score combines three dimensions into a value of 0-100: science (40%), practical experience (30%) and safety (30%). It is transparently derived from evidence level, attributed sources (PubMed/journals), legal classification and cautions. The FEI doping status is shown separately as a competition-law note and does not enter the score. Commissions and vendor relationships have no influence on the score. In addition, the editorial safety rating caps the result: it limits the safety dimension and the overall tier (orange: at most solid). For entries rated red, no score is calculated at all. The rating never raises anything — a green rating does not lift a calculated value.

An editorial assessment of the evidence and safety situation — not a healing claim and not an individual recommendation. It does not replace veterinary advice.

DosageNo established equine dose; in calming mixtures practice approx. 1–3 g/animal/day for a large horse (~500–600 kg). Coordinate with a vet.

AMG statusComplementary feed

FEI statusControlled (withdrawal)

Evidenceemerging

Usage note

This content is for information and education. It does not replace veterinary diagnosis or treatment. If your horse shows signs of illness, consult a veterinarian.

“Nothing forced can ever be beautiful.”

Xenophon · On Horsemanship (c. 365 BC)

Equiterna is an intermediary platform for equine knowledge, marketplace and tools — not a veterinary-medicines dealer, veterinary practice or pharmacy. Compound information is study-attributed and free of healing claims. Legal framework: Regulation (EU) 2019/6 / TAMG (DE/AT), Feed Regulation (EC) 767/2009, FEI Prohibited Substances List, HWG.