AN EVALUATION OF GARLIC AND ONION AS ANTITHROMBOTIC AGENTS

Garlic (Allium sativum) and onion (Allium cepa) have been evaluated as possible antithrombotic agents. Rats were given aqueous extracts of g arlic and onion, orally or intraperitoneally, daily for a period of 4 weeks after which the rats were sacrificed. The blood was collected fr om the heart without anticoagulant and the serum was prepared. The lev el of thromboxane B-2 (TXB(2)) in the serum was measured by radioimmun oassay. TXB(2) levels in serum of rats treated with the low dose of aq ueous extract of garlic (50 mg/kg) was significantly inhibited regardl ess of the mode of administration (orally or intraperitoneally). At th e high dose of garlic and onion (500 mg/kg), a further decrease of TXB (2) levels in the serum of the rats was observed. Boiled garlic and on ion at high concentration (500 mg/kg) had very little effect on TXB(2) synthesis. This shows that garlic and onion should be consumed in a r aw rather than cooked form in order to achieve a beneficial effect. Bo iling of these plants may cause the decomposition of the potential ant ithrombotic ingredient present in these herbs. Garlic was found to be more potent than onion in lowering the TXB(2), levels. A high dose of garlic and onion produces toxicity in the rats (unpublished observatio n). These results show that garlic and onion can be taken frequently i n low doses without any side effects, and can still produce a signific ant antithrombotic effect.