Morphine injections for cancer patients do not usually lead directly to death. Morphine is a central analgesic, an anesthetic with a particularly strong analgesic effect, and can be used for severe pain caused by trauma, cancer, burns, surgery, and pain caused by angina. Adverse reactions are headache, dizziness, vertigo and vomiting, impaired consciousness, constipation, impotence, insomnia and even coma. Morphine is contraindicated in patients with craniocerebral trauma, obstructive lung disease, pulmonary heart disease, hypothyroidism, prostate hypertrophy, and hepatic hypoplasia. Patients with cancer should use morphine under the guidance of a physician’s interview, do not use the drug privately, and report to the doctor in a timely manner if they become unwell.