HAEMOSTATIC AGENTS

HAEMOSTATIC AGENTS enhance the process of haemostasis, which is the arrest of blood loss from damaged blood vessels, and is essential to life. It involves three key components and their processes: platelets, blood vessels (the vascular endothelium and smooth muscle of the wall), and the blood-borne coagulation cascade system. To an extent, these components can be separated, but proper formation of the haemostatic plug in vivo requires interaction of all. For instance, blood coagulation in vitro is rapid and efficiently forms a clot as such, but it is not the same entity as the thrombus of platelets enmeshed in fibrin that constitutes the functional haemostatic plug which is required in haemostasis to prevent haemorrhage. Similarly, in vivo, in a patient with a deficiency of platelets, there may be spontaneous bleeding giving a purple coloration in the skin (thrombocytopenic purpurea); though the clotting time of the blood is unchanged, the bleeding time is prolonged. The processes involved in formation of fibrin are described in more detail at ANTITHROMBINS and ANTICOAGULANTS. Briefly, some agents are direct-acting thrombin antagonists, binding avidly to this enzyme and thus preventing the key stage in blood coagulation Read more […]

Zingiber officinale

Roscoe (Zingiberaceae) Common Ginger Description Zingiber officinale Roscoe is an herbaceous plant that grows up to 1.2 m high and with an underground rhizome. The stem grows above ground and leaves are narrow, long, lanceolate, with distinct venation pattern and pointed apex. Flowers are white or yellowish-green, streaked with purple and fragrant. Origin Originate from tropical Asia, widely cultivated in the tropics. Phytoconstituents Gingerol, zingiberene, farnesene, camphene, neral, nerol, 1,8-cineole, geranial, geraniol, geranyl acetate and others. Traditional Medicinal Uses Ginger is the folk remedy for anaemia, nephritis, tuberculosis, and antidote to Arisaema and Pinellia. Sialogogue when chewed, causes sneezing when inhaled and rubefacient when applied externally. Antidotal to mushroom poisoning, ginger peel is used for opacity of the cornea. The juice is used as a digestive stimulant and local application in ecchymoses. Underground stem is used to treat stomach upset, nausea, vomiting, nose bleeds, rheumatism, coughs, blood in stools, to improve digestion, expel intestinal gas, and stimulate appetite. The rhizomes are used to treat bleeding, chest congestion, cholera, cold, diarrhoea, dropsy, dysmenorrhoea, Read more […]

Herb-Drug Interactions: Ginkgo

Ginkgo biloba L. (Ginkgoaceae) Synonym(s) and related species Fossil tree, Kew tree, Maidenhair tree. Salisburia adiantifolia Sm., Salisburia biloba Hoffmanns. Pharmacopoeias Ginkgo (US Ph 32); Ginkgo capsules (US Ph 32); Ginkgo dry extract, refined and quantified (British Ph 2009, European Ph 2008); Ginkgo leaf (British Ph 2009, European Ph, 6th ed., 2008 and Supplements 6.1, 6.2, 6.3 and 6.4); Ginkgo tablets (US Ph 32); Powdered ginkgo extract (The United States Ph 32). Constituents Ginkgo leaves contain numerous flavonoids including the biflavone glycosides such as ginkgetin, isoginkgetin, bilobetin, sciadopitysin, and also some quercetin and kaempferol derivatives. Terpene lactones are the other major component, and these include ginkgolides A, B and C, and bilobalide, Ginkgo extracts may be standardised to contain between 22 and 27% flavonoids (flavone glycosides) and between 5 and 12% terpene lactones, both on the dried basis. The leaves contain only minor amounts of ginkgolic acids, and some pharmacopoeias specify a limit for these. The seeds contain ginkgotoxin (4-O-methylpyridoxine) and ginkgolic acids. Use and indications The leaves of ginkgo are the part usually used. Ginkgo is often used Read more […]

Policosanol: Clinical Use. Dosage

Most clinical studies have been conducted in Cuba with policosanol derived from sugar cane. HYPERLIPIDAEMIA Numerous randomised, double-blind clinical trials conducted prior to 2005 demonstrated significant cholesterol-lowering effects of oral policosanol; however, one recent study has produced negative results. Several previous studies conducted with postmenopausal women have confirmed efficacy in this population. Overall, these results show that a daily dose of 5 mg policosanol may: • reduce LDL-cholesterol by 11 -18% • reduce total cholesterol by 8-1 5% • increase HDL by 8-1 5% Whereas a higher dose of 20 mg policosanol daily can: • reduce LDL-cholesterol by 31% • reduce total cholesterol by 23% • increase HDL by 27%. Recent controversy It is important to note that previous research had been conducted almost entirely by the same research group in Cuba and involved Hispanic patients. In 2006, Berthold et al conducted a 12-week randomised study of 143 Caucasian subjects with hypercholesterolaemia or combined hyperlipidaemia. In contrast to previous studies, policosanol failed to significantly reduce LDL-cholesterol, total cholesterol, HDL-cholesterol, triglycerides and other lipid Read more […]