I. Why does advanced cancer produce pain? Cancer patients generally have the following three reasons for pain: 1. Tumor-related pain: caused by direct tumor invasion and compression of local tissues, tumor metastasis involving bone and other tissues. 2. 2. Anti-tumor treatment-related pain: it is commonly produced after surgery, traumatic examination operation, radiation therapy, and cytotoxic chemotherapy drug treatment. Non-tumor factor pain: including other comorbidities, complications and other pain caused by non-tumor factors. What is the harm of pain? Pain is one of the most common symptoms of cancer patients, which seriously affects the quality of life of cancer patients. The incidence of pain in advanced cancer patients is about 60%-80%, and 1/3 of them have severe pain. If cancer pain is not relieved, patients will feel extremely uncomfortable, which may cause or aggravate patients’ symptoms such as anxiety, depression, fatigue, insomnia, loss of appetite, etc., seriously affecting patients’ quality of life. Third, do cancer patients have to endure pain? For a long time, doctors, patients and their families still have not fundamentally changed the concept of cancer pain, that cancer patients should be pain, pain should be able to tolerate on endurance, fear of the application of morphine, for fear of addiction, for fear of the emergence of side effects, the concept of many cancer patients to endure great pain to walk through the last course of life, the quality of survival is extremely poor, these misconceptions must be fundamentally changed. Cancer patients have the right to ask for pain treatment, medical personnel have the obligation to control the pain of patients, try to make cancer patients pain-free, live with dignity and quality. IV. What are the principles of pharmacological analgesic treatment for cancer patients? According to the World Health Organization Guidelines for Three-Step Pain Relief Treatment for Cancer Pain, the five basic principles of pharmacological pain relief treatment for cancer pain are as follows: 1. Oral administration. 2. Administering drugs according to the ladder. It means that analgesic drugs of different strengths should be targeted according to the degree of pain of patients. 3, on time medication. Refers to the regular administration of pain medication at prescribed intervals. Timed administration helps to maintain a stable and effective blood concentration. At present, the clinical use of controlled-release drugs is becoming more and more widespread, emphasizing the control of slow-release opioid drugs as the basis of pain relief methods. Individualized drug administration. It refers to the formulation of individualized drug administration plan according to the patient’s condition and the dosage of cancer pain relief drugs. 5. Pay attention to specific details. The patients using painkillers should be monitored closely to observe the degree of pain relief and body reaction, and take necessary measures in time to minimize the adverse effects of drugs, with a view to improving the quality of life of patients. V. Is there any limitation on the dose of morphine applied to cancer patients? Morphine and its similar drugs are commonly used in the treatment of cancer pain, and there is no limit on the amount of morphine applied to cancer patients for pain control. In other words, morphine dosage is given as needed, and in order to achieve the goal of adequate relief of cancer pain, the required morphine dose can be unrestricted. Is morphine addictive to cancer patients? The sensitivity of human body to morphine varies greatly among individuals, some patients only need to use a very small dose to relieve pain, while others need to use a much larger dose to achieve the same effect. The medication should be used gradually starting from a small dose and continuously adjusted until the pain is satisfactorily controlled. Practice has proved that the phenomenon of addiction caused by the application of morphine-like drugs in the treatment of cancer pain is extremely rare. What are the side effects of morphine drugs? Adverse effects of morphine mainly include: constipation, nausea, vomiting, drowsiness, itching, dizziness, urinary retention, delirium, cognitive impairment, respiratory depression and so on. Except for constipation, most of the adverse effects of opioids are temporary or tolerable. VIII. Why is Dulcolax not advocated for pain relief in cancer patients? Dulcolax has poor analgesic effect, short duration of action, and high accumulation toxicity in long-term application, therefore, it is not advocated to apply Dulcolax analgesic treatment for cancer patients.