为了充分发挥药物的效用,根据药性及特点,故常常对汤剂内的某些药物采取先煎、后下等方法。先煎:如磁石、代赭石、龙骨、牡蛎、龟板等矿石、贝壳类药物,因为这些药物,质重难煎,所以应打碎先煎数沸,然后再下其他药物。象生半夏、生附子等有毒药物,也应先煎一小时,才能减低其毒性。 In order to give full play to the effectiveness of drugs, according to the nature and characteristics of drugs, it is often used in the decoction of some drugs to take the first fried, after the next method. First fried: such as magnets, substitutes, vermiculite, oysters, turtle shells and other minerals, shellfish drugs, because these drugs, difficult to fry the weight, so should be broken before frying a few boiling, and then under other drugs. Like poisonous drugs such as Pinellia terrestris and Aconite, they should be fried for one hour before they can reduce their toxicity.