Does NSAID use affect the Faecal Calprotectin Result?

In a word – yes!

Is this clinically significant? in another word, no!

Most non-steroidal anti-inflammatory drugs (NSAID) cause gastric damage in short-term volunteer studies, ranging from erythema to ulcers. Recent estimates suggest that gastrointestinal (GI) bleeding attributable to nonselective NSAID accounts for nearly 34% of all GI bleeding cases (mostly upper GI bleeding) in the US and may have resulted in over 32,000 hospitalisations per year during the last decade.

It would be logical therefore, since faecal calprotectin is a sensitive marker for inflammation in the gut, that a patient on NSAID would have a higher calprotectin level than would normally be seen.

In 1999, Tibble et al.1 showed that, whilst calprotectin concentrations were increased in 312 patients taking NSAID, the concentrations were still considerably lower than those seen in patients with active ulcerative colitis or Crohn’s disease. The use of faecal calprotectin in diagnosing NSAID enteropathy has been documented several times since the study of Tibble et al. was published.

In 2007, Goldstein et al.2 stated that the increase in mean faecal calprotectin concentrations after exposure to ibuprofen supports the concept of short-term development of intestinal inflammation with these drugs. The similar study by Maiden et al.3 regarding diclofenac also concluded this: celecoxib was also associated with a significant increase in faecal calprotectin concentration compared with baseline, but this difference was much lower compared with the mean change in concentrations observed in the ibuprofen group.

Thus, the question being asked is – what do you do with patients who are on NSAID and are having their faecal calprotectin concentration measured? Typically, concentrations are doubled in patients who are on NSAID but, in clinical practice, this does not have a large effect on the management of the patient. With a patient with IBS, the concentrations will typically be in the ‘grey zone’ of 50- 150 μg/g faeces. In these cases (as with any results in the grey zone), it is always advisable to repeat the test in a 2-3 months to make sure that there is no other clinical reason for such a concentration.

For those patients who are known to be on NSAID, clinicians have suggested that they should cease taking the drug for 3 weeks before collecting a faecal sample and sending it for analysis.

This article was published previously in Alpha Laboratories’ Leading Edge Newsletter – Summer 2014.

Click here to read more diagnostic articles published in Leading Edge



1. Tibble JA, et al. High prevalence of NSAID enteropathy as shown by a simple faecal test. Gut 1999;45:362-6.

2. Goldstein JL, et al. Small bowel mucosal injury is reduced in healthy subjects treated with celecoxib compared with ibuprofen plus omeprazole, as assessed by video capsule endoscopy. Aliment Pharmacol Ther 2007;25:1211-22.

3. Maiden L et al. A quantitative analysis of NSAID-induced small bowel pathology by capsule enteroscopy. Gastroenterology 2005;128(5):1172-8.