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Energy drinks are more popular these days than perhaps ever before. While the brunt of the “energy” in energy drinks comes from a combination of caffeine and/or sugar, beverage manufacturers often include other “bonus” ingredients to further the energy high. One of the most common additional supplements found in energy drinks is guarana.


What it does

Guarana (paullinia cupana) is a climbing shrub native to the Amazon basin whose fruit is regarded for its medicinal, antioxidative, and stimulatory qualities[1]. The brunt of guarana’s stimulatory kick comes from caffeine — the most popular (legal) psychoactive compound in the world.

While we tend to get our fix of caffeine from coffee, pre-workouts, or energy drinks, guarana packs quite a lot. In fact, depending on how the guarana extract is prepared, it may contain more than four times the amount of caffeine present in coffee beans[2].

Similar to coffee, guarana is also packed with additional stimulants, including theophylline and theobromine, which synergize with caffeine to promote smoother, long-lasting energy and focus. Guarana contains antioxidants as well to help defend against oxidative stress.

How it works

As said above, guarana contains caffeine, theobromine, and theophylline, which have been noted to block adenosine receptors[6]. Adenosine is an inhibitory neurotransmitter in the brain that acts as a CNS depressant when it binds to the adenosine receptor.

Since caffeine and theobromine are structurally similar to adenosine, they can bind to the adenosine receptors, thereby preventing adenosine from binding and thus calming the CNS down.

As a result of this inhibition (blockade) of adenosine receptors, guarana increases energy and alertness. And, since caffeine also stimulates dopamine release in the brain, guarana can also heighten mood, motivation, and focus.


More studies are needed to identify an “ideal dose” of guarana extract. However, the ingredient is typically supplemented in doses ranging 37.5-300mg[4].


  1. Schimpl F, Silva J, Goncalves J, Mazzafera P (2013) Guarana: revisiting a highly caffeinated plant from the Amazon. J Ethnopharmacol 150: 14–31. 10.1016/j.jep.2013.08.023
  2. Moustakas D, Mezzio M, Rodriguez BR, Constable MA, Mulligan ME, Voura EB. Guarana provides additional stimulation over caffeine alone in the planarian model. PLoS One. 2015;10(4):e0123310. Published 2015 Apr 16. doi:10.1371/journal.pone.0123310
  3. Dalonso, N., & Petkowicz, C. L. de O. (2012). Guarana powder polysaccharides: Characterisation and evaluation of the antioxidant activity of a pectic fraction. Food Chemistry, 134(4), 1804–1812
  4. Haskell, C. F., Kennedy, D. O., Wesnes, K. A., Milne, A. L., & Scholey, A. B. (2007). A double-blind, placebo-controlled, multi-dose evaluation of the acute behavioural effects of guarana in humans. Journal of Psychopharmacology (Oxford, England), 21(1), 65–70
  5. Baratloo A, Rouhipour A, Forouzanfar MM, Safari S, Amiri M, Negida A. The Role of Caffeine in Pain Management: A Brief Literature Review. Anesth Pain Med. 2016;6(3):e33193. Published 2016 Mar 26. doi:10.5812/aapm.33193
  6. Biaggioni, I., Paul, S., Puckett, A., & Arzubiaga, C. (1991). Caffeine and theophylline as adenosine receptor antagonists in humans. The Journal of Pharmacology and Experimental Therapeutics, 258(2), 588–593