Morphine has a strong inhibitory effect on the central nervous system, morphine belongs to opioid drugs, and its use is currently restricted in clinical practice. Morphine has a strong analgesic effect, for postoperative patients analgesia has a very good effect, the respiratory center and cough center has an inhibitory effect, the patient has a severe cough can be given morphine, but it is recommended that under the guidance of a physician, so as not to cause dependence or morphine overdose. For morphine overdose, the patient can experience severe headache, nausea, if morphine overdose is severe, it can inhibit respiration, leading to respiratory failure and death. Morphine has a certain effect on the smooth muscle and cardiovascular system, morphine can make the smooth muscle of the digestive tract excited, which can lead to constipation, and on the cardiovascular system, it can lead to peripheral vasodilatation, and blood pressure drop. However, because morphine is addictive, its use is restricted in clinical practice.