Abstract

Here we present a case of hypercalcaemia mimicking opioid toxicity. This is a 50 year old lady with a neuroendocrine tumour who presented with worsening back pain, thoracic wall pain, constipation, fatigue, confusion and nausea. Her regular morphine dose had recently been increased and she was initially admitted to hospice for management of these symptoms, which were believed to be due to opioid toxicity. However, investigations showed hypercalcaemia and she was treated adequately for this. Her symptoms were well controlled, although she continued to deteriorate due to the underlying malignancy and she remained on opioids for her end-of-life pain management. Hypercalcaemia and opioid toxicity have several overlapping symptoms, including fatigue, confusion, nausea and vomiting, constipation and abdominal pain. However there are specific signs and symptoms to help distinguish the two. Specifically, opioid toxicity can cause respiratory depression, miosis and myoclonic jerks while hypercalcaemia can cause bone pain, renal colic, arrhythmias, polyuria and polydipsia. Therefore attention should be paid to these specific features on assessment of patients and blood tests should be done if there is any uncertainty.

Keywords: Hypercalcaemia; Nausea; Opioid toxicity; Morphine; Curative treatment