Xanthine-containing Herbs

Xanthine-containing Herbs

Introduction:
Several herbs contain methylxanthines (theophylline, caffeine, theobromine). These substances have several pharmacological actions including CNS stimulation, relaxation of smooth muscle (especially bronchial muscle), myocardial stimulation, peripheral vasoconstriction and diuresis. They are infrequently used by herbalists as mild stimulants; widespread consumption of tea and coffee beverages is the most common mode of consumption. Frequently, they are added to "natural" energy-boosting products, occasionally with misleading labels such as "caffeine free".

pharmacology of xanthines:
The mechanism of action of xanthines is not fully understood but thought to involve several factors including adenosine receptor antagonism, modulation of intracellular calcium, phosphodiesterase inhibition, with central, vagal vasomotor and respiratory center actions. Toxicity is low, side effects include insomnia, anxiety, restlessness, tachycardia and extrasystoles and tachypnea.

Note: Xanthine-containing herbs are grouped by some authors with other types of herbal central nervous stimulants such as sympathomimetic herbs, here treated as a separate group, see Sympathomimetic Herbs

overview of interactions:
* herb affecting drug toxicity: Ephedrine and Epinephrine

* herbal concerns: Hypertensive and Tachycardic Herbs

* herb affecting drug toxicity: Monoamine Oxidase Inhibitors

* herbal concerns: Sympathomimetic Herbs

* herbal concerns: Vasoconstrictor Herbs

* herbal concerns: Sedative Herbs

herb affecting drug toxicity: Ephedrine and Epinephrine
* mechanism: Xanthine-containing herbs may additively interact with Epinephrine to further elevate catecholamine levels.

herb affecting drug toxicity: Monoamine Oxidase Inhibitors
* mechanism: Xanthine-containing herbs may additively interact with Monoamineoxidase inhibiting drugs to further elevate catecholamine levels.

herbal concerns:
Indirect interaction with other herbs may take place through various synergistic physiologic mechanisms with herbs in the following groups:
* Hypertensive and Tachycardic Herbs
* Sympathomimetic Herbs
* Vasoconstrictor Herbs

herbal concerns:
Xanthine-containing herbs, especially consumed as beverages, may antagonize effects of Sedative herbs

Common herbs containing Xanthines:
* Camellia sinensis (Tea)
* Coffea arabica (Coffee beans)
* Cola nitida (Kola)
* Ilex paraguariensis (Mat?)
* Paullinia cupana (Guarana)
* Theobroma cacao (Cacao)

Restricted or unusual herbs containing Xanthines:
* Banisteriopsis inebrians
* Davilla rugosa
* Euonymus europaeus
* Erodium spp.
* Genipa spp.
* Lippia multiflora
* Maytenus spp.
* Sterculia spp.
* Tylophora mollissima
* Villaresia spp.

References:

Brinker F. Herb Contraindications and Drug Interactions. Second edition., Sandy, OR: Eclectic Institute Inc, 1998.

Hardman J, et al. (eds.) Goodman &Gilman's Pharmacological Basis of Therapeutics. Ninth edition. McGraw Hill, 1996.

McGuffin M, et al. (eds.) AHPA Botanical Safety Handbook . CRC Press, 1997.

Mills SY. Out of the Earth: The Essential Book of Herbal Medicine. London: Arkana, 1991.