Is morphine the drug of choice in cancer pain?

Pharmacological treatment of bowel obstruction in cancer patients

INTRODUCTION

Malignant bowel obstruction (MBO) is a common complication of advanced cancer, occurring most frequently in gynaecological and colorectal cancer. Its management remains complex and variable. This is in part due to the lack of evidence-based guidelines for the clinicians involved. Although surgery should be considered the primary treatment, this may not be feasible in patients with a poor performance status or advanced disease. Advances have been made in the medical management of MBO which can lead to a considerable improvement in symptom management and overall quality of life.

AREAS COVERED

This review emphasizes the importance of a prompt diagnosis of MBO with early introduction of pharmacological agents to optimize symptom control. The authors summarize the treatment options available for bowel obstruction in those patients for whom surgical intervention is not a feasible option. The authors also explore the complexities involved in the introduction of parenteral hydration and total parenteral nutrition in this group of patients.

EXPERT OPINION

It is not always easy to distinguish reversible from irreversible bowel obstruction. Early and aggressive management with the introduction of pharmacological agents including corticosteroids, octreotide and anti-cholinergic agents have the potential to maintain bowel patency, and allow for more rapid recovery of bowel transit. A combination of analgesics, anti-emetics and anti-cholinergics with or without anti-secretory agents can successfully improve symptom control in patients with irreversible bowel obstruction.

Transdermal fentanyl: informed prescribing is essential

While morphine is historically the gold standard for the management of severe cancer pain, some patients either do not achieve adequate analgesia, or suffer intolerable side-effects. For these patients an alternative opioid is recommended. One such alternative is the potent mu opioid agonist fentanyl, delivered in a transdermal controlled release formulation. Similar to morphine, transdermal fentanyl is effective for the management of moderate to severe cancer pain. However, inappropriate prescribing of transdermal fentanyl, particularly in the clinical setting of unstable pain, can cause significant opioid toxicity, as highlighted in the case reports described.