Herb-Drug Interactions: Garlic

Allium sativum L. (Alliaceae) Synonym(s) and related species Ajo, Allium. Pharmacopoeias Garlic (US Ph 32); Garlic Delayed Release Tablets (US Ph 32); Garlic Fluid Extract (US Ph 32); Garlic for Homeopathic Preparations (British Ph 2009, European Ph 2008); Garlic Powder (European Ph, 6th ed., 2008 and Supplements 6.1, 6.2, 6.3 and 6.4, British Pharmacopoeia 2009); Powdered Garlic (US Ph 32); Powdered Garlic Extract (The United States Ph 32). Constituents Garlic products are produced from the bulbs (cloves) of garlic and are usually standardised according to the content of the sulphur-containing compounds, alliin, allicin (produced by the action of the enzyme alliinase on alliin) and/or γ-glutamyl-(S)-allyl-L-cysteine. Other sulphur compounds such as allylmethyltrisulfide. allylpropyldisulfide, diallyldisulfide, diallyltrisulfide, ajoene and vinyldithiines, and mercaptan are also present. Garlic also contains various glycosides, monoterpenoids, enzymes, vitamins, minerals and flavonoids based on kaempferol and quercetin. Use and indications Garlic has been used to treat respiratory infections (such as colds, flu, chronic bronchitis, and nasal and throat catarrh) and cardiovascular disorders. It is believed Read more […]


ADENOSINE RECEPTOR AGONISTS act extra cellularly at receptors variously known as adenosine receptors, P1 purine receptors, P1 receptors, P1 purinoceptors, or nucleoside receptors. Adenosine receptors have a wide range of mainly inhibitory actions in the body, including cardiac slowing, a fall in blood pressure, dilation of bloqd vessels, inhibition of platelet aggregation, inhibition of intestinal movements and actions within the central nervous system. Subtypes of adenosine receptors exist — A1, A2 and A3 — which have differential sensitivities to adenosine nucleoside analogues, including 2-methylthio-AMP, 2-thioadenosine, DPMA, IB-MECA, NECA, CPA, CCPA and DPCPX. These receptors, and subtypes within A2, have all been cloned. They have structures typical of the seven-transmembrane G-protein-coupled superfamily of receptors, but have amongst the shortest sequences known (A3 has only 318 amino acids), and a lack of sequence similarity with any other receptors appears to put them in a class of their own. Adenosine receptors are not sensitive to nucleotides such as ADP (adenosine diphosphate) and ATP (adenosine triphosphate), which instead act as P2 receptor agonists that are nucleotide-preferring (see P2 receptor Read more […]