Colonoscopy before the drug preparation as follows: 1, general colonoscopy: the day before the examination 20:00 ~ 21:00, Hengkang Zhengqing 1 box plus 1000 ml of warm water dilution after one hour to drink. The day of the examination 8:30 ~ 9:30 fasting, Hengkang Zhengqing 2 boxes plus more than 2000 ml of warm water dilution after one hour to drink, drink more plain water, more walking. One hour later 30ml bottle of ximethicone oil warm water delivery (drink a sip of warm water to flush). 2, painless colonoscopy: the day before the examination 16:00 ~ 17:00, Hengkang Zhengqing 1 box plus more than 1000 ml of warm water dilution after an hour to drink. 6:00~7:00 on the day of examination, Hengkang Zhengqing 2 boxes plus more than 2000ml of warm boiled water dilution after one hour to drink, one hour after 30ml a bottle of ximethicone oil warm water delivery (drink a mouthful of warm water to flush). Drink more plain water before ten o’clock, more walking, no water after ten o’clock, fasting that day, can be rehydrated. 3, the day before the examination into the dregs-free semi-liquid: thin rice, noodles, forbidden sweets, dairy products, seaweed, leeks, celery and seeded fruits. 4.If there are antispasmodic drugs such as Desutex, Spamin, etc., please take them orally three days before the examination as prescribed by the doctor. 5.If you are taking aspirin, please stop taking it for one week before the examination. Painless gastroscopy, general gastroscopy drink 15ml half bottle of simethicone oil 30 minutes in advance, the remaining half bottle to drink after gastroscopy. Colonoscopy, drink 30ml bottle of simethicone oil 1 hour after drinking the purgative, served with warm water (drink a sip of warm water to flush).