guarana (Paullinia cupana, Brazilian cocoa, Zoom)

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GENERIC NAME: guarana gum

BRAND NAME: Paullinia cupana, Brazilian cocoa, Zoom

DRUG CLASS AND MECHANISM: Guarana is a natural herbal supplement. The exact mechanism of how guarana works is not known. Guarana contains more than 2.5% to 5% caffeine by weight. Caffeine is a stimulant and is most likely responsible for most of guarana's effects. There is no scientific evidence that guarana extracts or berries contain any other therapeutical use. Check with your health care professional before using herbs or herbal supplements.



PREPARATIONS: Guarana is available in tablets, capsules, powder extract, seed extract, and in beverage forms. Concentrations of guarana may vary from product-to-product due to multiple manufacturers producing various products.

STORAGE: Due to multiple manufacturers making different forms of Guarana, storage requirements may vary based on individual manufacturer practices.

PRESCRIBED FOR: Guarana is used for weight loss, to reduce fatigue, and treat diarrhea. It is also used as a diuretic, to improve athletic performance, and to improve cognitive function.

DOSING (may vary with supplier):

  • Weight loss: Take 200 to 1600 mg of seed extract by mouth once daily. Not to exceed more than 3 grams per day.
  • Cognitive improvement: Take 150 mg of standardized dry extract by mouth once daily.
  • Energy improvement: Take 200 to 800 mg by mouth before breakfast or lunch once daily. Not to exceed more than 3 grams per day.
  • Diuretic: Take 486 mg by mouth once daily.
  • Diarrhea or dysentery: Take 1 gram by mouth up to 4 times a day.

DRUG INTERACTIONS: Guarana should be used with caution with medications like caffeine, green tea, armodafinil (Nuvigil), modafinil (Provigil), phentermine (Adipex-P), methylphenidate (Methylin), and amphetamine and dextroamphetamine (Adderall, Adderall XR). Combining these drugs with guarana may increase heart rate, anxiety, headache, and agitation. Individuals should check with their physicians before using this supplement.

PREGNANCY: There are no adequate studies done on guarana determine safe and effective use in pregnant women.

NURSING MOTHERS: It is not known whether guarana enters breast milk; therefore, it is best to avoid using it in nursing mothers.

SIDE EFFECTS: Side effects of guarana are agitation, anxiety, increased heart rate, abnormal heart rhythm, diarrhea, nausea, vomiting, and stomach cramps.


Medscape. Guarana (Herbs/Suppl) - Brazilian cocoa, guarana gum, guarana paste, guaranine, paullinia cupana, Uabano, Uaranzeiro, zoom.

Woods, DJ. Guarana: Paullinia cupana, P. sorbilis; also known as Brazilian cocoa and 'zoom'. J Prim Health Care. 2012 Jun 1;4(2):163-4.

Medically Reviewed by a Doctor on 8/11/2014

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