Guarana provides additional stimulation over caffeine alone in the planarian model.

Guarana in Combination with Glucose and Caffeine Provides a Short-Term Stimulus at Low Concentrations Upon an assessment of locomotor velocity using guarana seed extract together with caffeine and glucose ( Fig 7 ) we observed a slightly significant increase using low concentrations (0.001 mM for each guarana and caffeine, with 0.561 mM glucose) after only two minutes of habituation (p = 0.041).

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