Issues for surgery
For regular, chronic use – risk of rebound hyperacidity if omitted.
Increased risk of acid aspiration and/or post-operative stress-related mucosal disease if omitted.
For investigations of Helicobacter pylori (H. pylori) associated dyspepsia – risk of false negative if continued.
Advice in the perioperative period
Elective and emergency surgery
Continue.
Patients who take ‘when required’ famotidine should be advised to take a dose of their usual medication the evening prior to and/or on the morning of surgery.
EXCEPT: Investigations for H. pylori – stop 2 weeks prior to investigation.
For patients with increased risk factors for aspiration (e.g. pregnancy, obesity, non-fasted state in emergency surgery) consider administration of acid-suppressing medication (oral or intravenous) pre-operatively – see Further information. Please refer to specific product information on the dose(s) of famotidine to be administered pre-operatively.
Post-operative advice
Patients undergoing anti-reflux surgery or total gastrectomy
If patient is on famotidine, consider continued need for therapy following surgery.
Use of post-operative non-steroidal anti-inflammatory drugs (NSAIDs)
Consider prophylaxis with a histamine-2 receptor antagonist (H2RA) such as famotidine, if PPI not suitable, for patients commenced on NSAIDs for post-operative pain relief, especially in those that have increased risk factors for gastro-intestinal ulceration. Use the lowest possible dose. Discontinue famotidine treatment as soon as patient stops NSAID treatment.
Interactions with common anaesthetic agents.
None.
Interactions with other common medicines used in the perioperative period
Opioids
Famotidine may enhance the effects of some opioid analgesics (e.g. morphine, pethidine).
Further information
H2RAs vs. Proton Pump Inhibitors
Superiority of either class of acid-suppressing medication given perioperatively to reduce the risk of aspiration has not been definitively proven, although the majority of evidence supports the pre-operative administration of H2RAs in most patients, with PPI therapy being reserved for patients on chronic acid suppression who may have developed some degree of tolerance to such chronic acid suppression. Also see Proton Pump Inhibitors drug records.
References
Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 22nd June 2019]
Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 23rd June 2019]
Opioid Analgesics. In: Brayfield A (Ed), Martindale: The Complete Drug Reference. London: The Royal Pharmaceutical Society of Great Britain. http://www.medicinescomplete.com [Accessed 23rd June 2019]
Aspiration syndromes (Gastrointestinal Drugs – Management of Gastrointestinal Disorders). In: Brayfield A (Ed), Martindale: The Complete Drug Reference. London: The Royal Pharmaceutical Society of Great Britain. http://www.medicinescomplete.com [Accessed 23rd June 2019]
Medscape. Acid Suppression in the Perioperative Setting: Acid-Related Pulmonary Complications. www.medscape.org [Accessed 22nd June 2019]