The use of morphine to treat cancer-related pain: a synthesis of quantitative and qualitative research.

Morphine is the most commonly used opioid for severe cancer-related pain. Despite its established effectiveness, it is often used cautiously in clinical practice, particularly outside specialist palliative care. This review identifies the key social, contextual, and physical concerns held by patients, carers, and health care professionals when using morphine, which might explain the caution taken in its use. The review used an approach called critical interpretive synthesis (CIS), which combines conventional systematic review techniques with methods for interpretative synthesis of qualitative research. An existing review examining the effectiveness of morphine and a guideline on its use were synthesized with 19 qualitative articles to establish understanding of how context of use can affect the established effectiveness of morphine. The article argues for the appropriateness of CIS for answering questions of this type. The results demonstrate that using morphine is a balancing act and a trade-off between pain relief and adverse effects. Deep-seated concerns regarding the symbolism of morphine, addiction, and tolerance are held by patients, carers, and clinicians, which influence prescription and use. Cancer pain is a referent for disease status and has existential meaning, with the introduction of morphine becoming a metaphor for impending death. Cancer pain is intersubjective, with its perception and reporting influenced by those with whom the patient interacts. By understanding the context and social meaning surrounding the use of morphine to treat cancer pain, health care professionals can begin to anticipate, acknowledge, and address some of the barriers to its use, thereby enhancing pain control.