Herb-Drug Interactions: Mate

Ilex paraguariensis A. St.-Hil. (Aquifoliaceae)

Synonym(s) and related species

Ilex, Jesuit’s Brazil tea, Paraguay tea, St Bartholomew’s tea, Yerba mate.


Mate leaves contain xanthine derivatives, mainly caffeine (0.2 to 2%) and theobromine, with minor amounts of theophylline. They also contain various flavonoids of the flavonol subclass (quercetin, kaempferol and rutin), and polyphenolics, tannins and caffeic acid derivatives. Others include triterpenoid saponins and volatile oil.

Use and indications

Mate leaves are used as a stimulant, diuretic and analgesic, effects that can be attributed to the caffeine content. Mate is used to make a tea-like beverage in South America. High consumption of this tea appears to be associated with a high incidence of cancers of the oropharynx and oesophagus.


For the pharmacokinetics of caffeine, see caffeine. For information on the pharmacokinetics of individual flavonoids present in mate, see under flavonoids.

Interactions overview

The interactions of mate are mainly due to its caffeine content, see caffeine. For information on the interactions of individual flavonoids found in mate, see under flavonoids.