Guarana seeds

Information
Application
Notes
References

Botanical name

Paullinia cupana Kunth (Syn. Paullinia sorbilis Mart.)

Family

Sapindaceae

Common name

Guarana, Cupana, Brazilian cocoa

Information about the plant

The guarana plant is a woody climbing vine native to the Amazon region of Brazil and the Orinoco region of Venezuela, which has been used for centuries by the indigenous peoples living there. It is now cultivated in Colombia, Panama, Brazil, Venezuela, and Costa Rica, mostly as a climbing plant on supports, because its seeds are used to make refreshing and stimulating beverages.

Guarana is a climbing vine that grows up to 12 m tall in the jungle canopy. Its leaves are five-lobed, odd-pinnate, arranged oppositely on the branches. The flowers are yellow to whitish and form panicles up to 30 cm long. They are monoecious, slightly zygomorphic, with five elongated petals. After flowering, hazelnut-sized, orange-red, three-locular capsule fruits develop, which burst open when ripe. The rounded seeds, usually only one per capsule, are dark brown to almost black, shiny, and sit in a cup-shaped white seed coat (aril). This gives the seed in the opened fruit the appearance of a dark eye, which has inspired many legends. The seed itself is marked by a light spot, which represents the break point of the funiculus.

Medicinally used parts of plants (herbal drug)

Guarana seeds (Guaranae semen, Paulliniae semen) are used after they have been dried and the seed coat (aril) removed.

Guarana seeds are imported from Brazil, Venezuela, Colombia, Panama, and Costa Rica.

Constituents of the herbal drug

Guarana seeds contain purine alkaloids, mainly caffeine (3.6 to 6%), in addition to theobromine and theophylline, as well as catechin, epicatechin, and catechin tannins. Various mono- and sesquiterpenes are present in the volatile fraction. In addition, they contain fatty oil, cyanolipids, carbohydrates (starch, polysaccharides, etc.), proteins, and minerals.

Quality of the drug

The quality of guarana seeds (Guaranae semen) is specified in the European Pharmacopoeia (Ph. Eur.). In other publications (e.g., HMPC), the drug is also listed as “Paulliniae semen.”

A paste made from roasted and peeled seeds, kneaded with water, shaped into sticks, and dried, is also commercially available. This product, known as “pasta guarana” or “guaraná,” was previously listed in a monograph in Supplement 6 to the DAB. It contains 3 to 4.5% caffeine.

Medical applications

Recognised medical use

The HMPC has classified guarana seeds (Paulliniae semen) as a traditional herbal medicinal product (see “Traditional use”).

ESCOP: As a stimulant in cases of fatigue, exhaustion, or during recovery. These indications are based on human experience and long-standing use.

Traditional use

Guarana seeds (Paulliniae semen) have been classified by the HMPC as a traditional herbal medicinal product (Article 16a of Directive 2001/83/EC). Based upon long standing-use, guarana can be used internally to treat fatigue and feelings of weakness.

Herbal drug preparations in finished dosage forms

Powdered guarana seeds or “guarana paste” (see above) in capsules, tablets, drinkable ampoules

The powder is mainly used in food products, in various forms such as lozenges, drops, capsules, and chewing gum, or as a “stimulating” additive in fruit juices and other soft drinks.

Dosage

The dosage depends on the caffeine content of the preparation. The daily dose of caffeine should not exceed 400 mg.

ESCOP recommends a daily dose of 1 to 3 g of powdered guarana seeds. HMPC recommends up to 450 mg of guarana seeds five times a day, which corresponds to a daily dose of up to 2.25 g. Assuming a caffeine content of 5% in the seeds, the ESCOP dosage corresponds to a daily caffeine dose of 150 mg, while the HMPC dosage corresponds to a daily caffeine dose of 112.5 mg.

Preparation of a tea

Not applicable.

Notes

Guarana seeds should not be taken before bedtime due to their content of stimulating caffeine. Guarana seeds should not be used in cases of stomach or intestinal ulcers, high blood pressure, cardiac arrhythmia, or hyperthyroidism.

No studies are available on the safety of guarana seeds during pregnancy and lactation. The use in children and adolescents under 18 years of age has not been established due to lack of adequate data.

Side effects

None known.

Interactions

Persons taking MAO inhibitors should use guarana seeds with caution. Caffeine-containing preparations reduce sedative effects and increase side effects caused by sympathomimetic drugs.