The effect of magnesium sulfate to induce diarrhea is good, magnesium sulfate is a common diarrhea inducing drug, which is often used as a cleansing drug before colonoscopy. After this drug is taken, it can increase the osmotic pressure effect of the intestine and cause irritation to the colonic mucosa, leading to hyperactive peristalsis of the colon, so the contents of the colon can be expelled quickly. However, in the process of using magnesium sulfate, not only the intestine cannot absorb water, but also the phenomenon of water loss, which may even lead to dehydration. Therefore, when using magnesium sulfate to induce diarrhea, it is best to pay attention to replenish water at the same time, so that the effect of diarrhea is good, but also to avoid dehydration. Because of the relatively strong irritation of magnesium sulfate diarrhea, will have an impact on health, so the body is relatively weak people and infants, should try to avoid using.