Serious Adverse Drug Reactions to Long-Term Oral Liquid Morphine in Patients with Chronic Pain: A Cross-Sectional Survey in Palliative Care

Barbara Duncan,1 Germanus Natuhwera,1,2 Doris Nassuuna,3 Roselight Katusabe,1 Hanif Kasozi,1 Wilson Acuda2 1Clinical Department, Hospice Africa Uganda, Kampala, Uganda; 2Education Department, Institute of Hospice and Palliative Care in Africa, Kampala, Uganda; 3Research Department, International Rescue Committee, Kampala, UgandaCorrespondence: Germanus Natuhwera, Email [email protected]; [email protected]: Behaviour suggestive of addiction in some patients on long-term oral liquid morphine (OLM) caused concern amongst the Hospice Africa Uganda clinical team and prompted the survey. This survey aimed to identify serious adverse drug reactions to long-term OLM in patients with chronic pain receiving palliative care.Methods: In Phase 1, the database of patients receiving palliative care at Hospice Africa Uganda was analyzed to find patients taking OLM from 12.7.2017 to 19.10.2017. A purposive review of their medical records was undertaken to identify those on long-term OLM. Phase 2 was conducted between 12.6.2018 and 23.10.2018. All patients on long-term OLM were offered biopsychosocial and spiritual assessment by a pain specialist (BD) to determine whether they were experiencing any serious adverse drug reactions. Phase 3 immediately followed phase 2 assessment. The pain specialist discussed with the participant any medication changes (including OLM) or other therapies to facilitate holistic management of pain for the individual.Results: In phase 1, 653 patients on OLM were identified. Phase 2 identified 49 patients who were on long-term OLM. Thirty-four patients agreed to participate in the assessment with the pain specialist. Of the 34 participants, 24 had chronic non-cancer pain and two had chronic cancer pain. Eight cancer survivors had incidental chronic non-cancer pain. Serious adverse drug reactions were identified in four participants with chronic non-cancer pain. Two cases of addiction, one case of opioid hyperalgesia, and one probable diversion of morphine.Conclusion: To our knowledge, the study identified the first documented cases of addiction to OLM in sub-Saharan Africa. Future research involving a larger multicenter sample, longitudinal, and qualitative designs is needed. Education of healthcare practitioners prescribing opioids should put equal emphasis on management of chronic non-cancer pain as do chronic cancer pain to minimize the risk of serious adverse reactions.Keywords: chronic pain, opioids, oral liquid morphine, palliative care, serious adverse drug reactions