Use castor oil to cleanse the intestines, and drink water after drinking castor oil. Castor oil is the oil extracted from castor seeds, which itself has no direct excretory effect, but is hydrolyzed by lipase in the upper part of the small intestine, releasing a ricinolinic acid that stimulates the smooth muscle of the intestine and inhibits the absorption of water and electrolytes, thus playing the role of defecation. In addition to its purgative effect, castor oil also has a certain effect of reducing swelling and removing toxins, and can be applied externally to relieve canker sores and pains in the early and middle stages. It is important to note that castor oil should be contraindicated in pregnant and lactating women, as it may cause uterine contractions. It is not recommended for long-term use as it may cause excessive diarrhea or short term constipation. This drug should be used under medical supervision. Castor oil may interact with some drugs, such as fat-soluble dewormers, so self-medication is not recommended.