For widespread cancer pain, central nervous system morphine delivery can provide powerful relief with lower doses and fewer side effects, such as constipation.
Cancer is a common disease in Hong Kong, and many patients with advanced cancer have pain problems. Severe pain can make patients depressed and despondent. This can seriously affect patients’ quality of life during the final journey of their lives, and it also places significant stress on their caregivers.
Doctors usually prescribe morphine or morphine-type painkillers for such patients. But morphine may not always be a panacea.
The first issue is the misunderstanding of morphine among patients or their families. The author often hears patients say that if they use morphine, they will die soon. In fact, the length of the patient’s remaining life depends on the disease itself, not on morphine. On the contrary, in the author’s experience, cancer patients whose pain is well controlled tend to live longer.
In addition, many people, especially the elderly, may not be able to tolerate the side effects of morphine, such as severe constipation, vomiting, or drowsiness. There are also some patients receiving high doses of morphine whose pain-relieving effect is still unsatisfactory.
In fact, in addition to morphine, there are many other ways to help control cancer-related pain. The main principle is to use medication or heat to selectively disrupt the sensory nerves that transmit pain signals from the affected area. Common applications include cancer-related chest pain, upper abdominal pain, pelvic pain, and limb pain.
For widespread cancer pain that is poorly controlled with morphine or causes significant side effects, doctors may administer morphine or a local anaesthetic directly into the central nervous system. This method can be up to 100 times more potent than a standard morphine injection. Because much lower doses are required, it may reduce side effects such as severe constipation. A catheter is usually implanted and connected to an external infusion pump to deliver the medication.
Information provided by Dr. Lee Yuk-ming, Specialist in Pain Medicine
