Lactulose, Macrogols (Cosmocol®, Laxido®, Movicol®)
[This monograph does not cover use of osmotic laxatives for bowel cleansing in preparation for procedures that require a clean bowel]
Issues for Surgery
For prevention of hepatic encephalopathy – risk of impaired consciousness and encephalopathy if omitted.
Advice in the Perioperative period
Due to the volume of water required to reconstitute macrogol laxatives and the recommendation to drink around 1.5 – 2 litres of fluid with lactulose1; review if the patient is nil by mouth or under a fluid restriction in the post-operative period.
If concomitant use of opioids or other medication that may cause constipation, or antibiotics that may cause diarrhoea, monitor response to treatment and adjust dose accordingly.
Review if patient develops reduced gastrointestinal motility (e.g. ileus) post-operatively.
Patients undergoing Colorectal Surgery
Patients undergoing Head and Neck Surgery
Interaction(s) with Common Anaesthetic Agents
Interaction(s) with other Common Medicines used in the Perioperative Period
Addition of a macrogol (PEG)-based laxative to a liquid that has been thickened with a starch-based thickener may counteract the thickening action, resulting in a thin watery liquid that, when swallowed, increases the risk of potentially fatal aspiration in patients with dysphagia. Healthcare professionals are advised to avoid directly mixing macrogol-based laxatives with starch-based thickeners, especially for patients with dysphagia who are considered at risk of aspiration.