Bulk-forming Laxatives

Ispaghula husk, Sterculia

Issues for Surgery

Risk of oesophageal or intestinal obstruction if taken immediately before operation (see Further Information).

Risk of constipation if omitted for prolonged period, which may further be exacerbated by medications administered perioperatively e.g. opioids.

Advice in the Perioperative period

Elective and Emergency Surgery
Omit any dose(s) due on morning of operation (including combination products) – see Further Information.

Combination Products: -

Fybogel mebeverine® (mebeverine + ispaghula husk) – follow advice above but see also Antispasmodics (Smooth Muscle Relaxants) monograph
Manevac® (senna + ispaghula husk) – follow advice above but see also Stimulant Laxatives monograph
Normacol Plus® (sterculia + frangula) – follow advice above but see also Stimulant Laxatives monograph

Post-operative Advice
Resume post-operatively, if needed, once enteral intake resumed providing patient is not in a recumbent position and is maintaining adequate fluid intake (e.g., manufacturer of Fybogel® advises each sachet should be reconstituted with 150mL of fluid as inadequate fluid intake can result in oesophageal and intestinal obstruction¹).

If concomitant use of opioids or other constipating medications – monitor response to treatment and adjust dose accordingly.

Review if patient develops reduced gastrointestinal motility (e.g., ileus) post-operatively.

Patients undergoing Colorectal Surgery
Review the need for bulk-forming laxatives post-operatively.

Interaction(s) with Common Anaesthetic Agents

None^{1, 2, 3, 4,}.

Interaction(s) with other Common Medicines used in the Perioperative Period

None^{2, 3, 4}; however, enteral absorption of concomitantly administered medicines may be delayed by ispaghula husk¹. The manufacturer advises ispaghula husk should not be taken for 30-60 minutes before or after intake of other medicinal products to limit this effect¹.

Further Information

Safe Administration
Bulk-forming laxatives swell in contact with water; to prevent oesophageal or intestinal obstruction adequate fluid intake is essential and products should not be taken immediately before bed or if the patient is in a recumbent position^{1, 3}.

References

Summary of Product Characteristics – Fybogel® Orange Granules (ispaghula husk). Forum Health Products Limited. Accessed via www.medicines.org.uk 05/03/2021 [date of revision of the text December 2020]
Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 5^th March 2021]
Summary of Product Characteristics – Normacol® (sterculia). Norgine Limited. Accessed via www.medicines.org.uk 05/03/2021 [date of revision of the text December 2020]
Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 5^th March 2021]