Theacrine (Teacrine)

What it is

Like caffeine, theobromine and theophylline, theacrine belongs to the purine alkaloids, but it is not a methylxanthine; it is a methylated uric acid. The richest source is kucha, a special tea plant from China related to Assam tea. In young leaves and buds, researchers found about 2.8 percent theacrine in the dry matter, alongside 0.6 to 2.7 percent caffeine. The plant builds theacrine from caffeine. It is also found in some coffee species, especially Coffea liberica, and in the cupuaçu fruit.

The best-known branded ingredient, Teacrine, does not come from tea but is a synthetic, nature-identical version. It has been used in dietary supplements in the USA for years, for example in pre-workout products. It is often combined with caffeine and sometimes with methylliberine, another purine alkaloid from the coffee plant.

How it is supposed to work

The idea is the same as with caffeine: caffeine blocks adenosine receptors, thereby shifting the regulation of sleep and wakefulness and reducing the feeling of tiredness. Because of its similar structure, theacrine is supposed to act similarly. In a 2012 rat study, theacrine increased locomotor activity and reversed the dampening effect of adenosine agonists. Blockers of the dopamine D1 and D2 receptors weakened the effect, so it seems to involve the dopamine system as well. Important for the marketing: with repeated administration, the rats developed neither tolerance nor sensitization.

The animal data are, however, not consistent. In two mouse studies, theacrine was not stimulating, but prolonged the sleep induced by a sleeping drug and, in the EEG, prolonged non-REM sleep. A 2020 review explicitly speaks of inconsistent results. Which effect predominates in humans has never been measured directly at the receptors.

Beyond wakefulness, Chinese research groups in particular are interested in theacrine. In stressed mice, it had an antidepressant-like effect and promoted the formation of new nerve cells in the hippocampus. A review also mentions antioxidant and anti-inflammatory effects as well as influences on fat metabolism. All of this so far comes from cell and animal experiments and is a field for future human studies.

A real difference from caffeine is the kinetics. Theacrine reaches its peak concentration after about 2 hours and has a half-life of 16 to 26 hours, caffeine of 3 to 6 hours. In a study with 8 people, caffeine taken at the same time increased the amount of theacrine absorbed without changing the half-life. Conversely, theacrine did not affect caffeine kinetics.

What the studies show

Eight weeks of tolerability

In the longest study to date, 60 healthy young adults received one of two theacrine doses or placebo daily for 8 weeks. All safety markers remained within the normal range, and there was no sign of a declining effect or habituation. The study was funded by the manufacturer of the branded ingredient, which, according to the authors, was not involved in data collection and interpretation.

Strength training without effect

Twelve strength-trained men tested caffeine, theacrine, a combination and placebo before bench press, squats and rowing in a double-blind crossover study. No variant improved strength or endurance. Only caffeine alone increased the feeling of energy, by 15.3 percent compared with placebo; theacrine did not.

Soccer on the treadmill

In 24 high-level soccer players, a test to exhaustion was run after a simulated 90-minute match. With theacrine and with the combination, the players lasted 27 to 38 percent longer than with placebo, but the difference narrowly missed the significance threshold. Faster choice reaction time was seen with caffeine and with the combination.

Sleep and vigilance

In an Australian study without external funding, 22 men took seven variants over 45 days: placebo as well as a low and a high dose, each 12, 8 or 4 hours before going to bed. Night-time sleep did not change significantly. Those who had taken the high dose within 8 hours before sleep had fewer lapses in the vigilance test the next morning; reaction time remained the same.

High doses, more side effects

Two studies with 19 people each tested higher doses. In a 4 km cycling time trial, theacrine brought no advantage, but the higher dose increased resting blood pressure, and gastrointestinal complaints, a racing-heart sensation, dizziness, headache and tremor occurred. In the second study, the stress hormone cortisol in saliva rose; energy and cognition did not improve.

Where the data stop

So far, little speaks for athletic performance. Of five controlled studies with theacrine alone, four showed no effect, in strength, sprint, team sport tests, cycling time trials and canoe sprint. Only the soccer study found a trend. The feeling of energy is not consistently supported either: in two studies, it was no better with theacrine than with placebo.

All studies are small, short and conducted in healthy young people; several were funded by the manufacturer. Data beyond 8 weeks are lacking, as are studies in older people or people with pre-existing conditions. The mechanism in humans is inferred, not measured, and the animal experiments contradict each other between stimulating and sedating. The promise of caffeine without habituation rests essentially on one study.

Status, approval and legal

Theacrine is not authorized as a food ingredient in the EU. There is no entry in the EU Novel Food Catalogue, nor in the Union list of authorized novel foods. The Swedish food authority reported theacrine in dietary supplements as a novel food three times in 2020 and 2021 via the EU Rapid Alert System; there is no notification from Germany. Methylliberine, which is often added, is a non-authorized novel food according to the catalogue. Theacrine is not a medicine, not prescription-only and not a controlled narcotic. It is not on the 2026 WADA list; a 2025 analysis rates its anti-doping status as unclear. In the USA, it is on the market as an ingredient of dietary supplements.

Safety

In the usual study amounts, theacrine was well tolerated for up to 8 weeks, without changes in blood values, pulse and blood pressure. At higher study doses, resting blood pressure and cortisol rose, and side effects such as gastrointestinal complaints, a racing-heart sensation, headache and tremor occurred. Caffeine increases the amount of theacrine absorbed, so in combination products more theacrine reaches the blood than with theacrine alone. Because of the long half-life, late intake is theoretically a sleep issue, even though one study found no significant effect. Toxicological data to current standards are hardly publicly available. Pregnancy, breastfeeding, children and adolescents as well as people with high blood pressure, cardiac arrhythmias or anxiety disorders have not been studied; restraint is advisable for them, as it is with caffeine intolerance.

Sources

• Taylor et al., J Int Soc Sports Nutr 2016
• Ziegenfuss et al., J Diet Suppl 2017
• He et al., J Caffeine Adenosine Res 2017
• Feduccia et al., Pharmacol Biochem Behav 2012
• Cesareo et al., J Int Soc Sports Nutr 2019
• Bello et al., J Int Soc Sports Nutr 2019
• Gardiner et al., Sci Rep 2024
• Vieira-Cavalcante et al., Appl Physiol Nutr Metab 2025
• Lints et al., J Int Soc Sports Nutr 2025
• RASFF 2020.2471, Sweden: theacrine as a novel food