Bismuth Citrate Potassium Capsules are suitable to be taken before meals and at bedtime. Bismuth Citrate Potassium Capsules can be taken in two ways, i.e. four times a day or twice a day. If it is taken four times a day, the first three times are taken half an hour before three meals and the fourth time is taken two hours after dinner, which is roughly before bedtime. If it is taken twice a day, the first time is taken half an hour before breakfast and the second time is taken at bedtime. This is because the mechanism of action of bismuth citrate potassium capsules is to prevent the irritation of the ulcer surface by stomach acid, enzymes and food by dispersing into a protective film that covers the ulcer surface in the acidic environment of the stomach. After a meal, the secretion of stomach acid and enzymes increases, and the food in the stomach also increases, which increases the irritation of the ulcer surface. Therefore, bismuth citrate potassium capsule is suitable for taking before a meal, and after a meal, it can have an anti-ulcer effect.