綱目稱其行水瀉腎．仲景地黃丸用茯苓澤瀉者．取其瀉膀胱之邪氣．古人用補(bǔ)藥必兼瀉邪．邪去則補(bǔ)藥得力．后世不知此理．一意用補(bǔ)．故久服有偏勝之患．是澤瀉但長(zhǎng)于利水．未可專任．扁鵲云．多服病患眼．蓋小便利．腎氣虛．故昏目也．本草久服云云．揚(yáng)之太過(guò)．用者審之．