UK Clinical Pharmacy Association

Ispaghula husk

Issues for surgery

Risk of constipation if omitted, particularly in patients with chronic laxative use, which may further be exacerbated by medication administered perioperatively, e.g. opioids.

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

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 Mebeverine drug record.
  • Manevac® (senna + ispaghula husk) – follow advice above but see also Senna drug record.


  • for patients having bowel cleansing preparations prior to surgery – stop when bowel preparation starts.

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 obstruction).

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.

Interactions with common anaesthetic agents


Interactions with other common medicines used in the perioperative period

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

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.


Summary of Product Characteristics – Fybogel® Orange Granules (ispaghula husk). Reckitt Benckiser Healthcare (UK) Ltd. Accessed on 23 March 2024 via [Date of revision of the text December 2020]

Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. [Accessed on 23 March 2024]

Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. [Accessed on 23 March 2024]