Table 1.

Summary of interventions, study details, results and quality of evidence

Source	N (Intervention: Placebo)	Study Type	PI-IBS inclusion criteria	Intervention (Type, dose, length of intervention, frequency)	Duration of intervention	Outcome(s)	Quality of evidence (modified GRADE [17])
Bafutto et al., 2011	61 (18:43)	cohort	Rome III with IBS-D, as reported by patient	- Mesalazine	30 days	- stool frequency decreased by 1.33 stools/day on average	Moderate
				- 30 days			The study is unclear as to how the randomization and allocation concealment were conducted.
				- 800 mg
				- TID
						- stool form and consistency improved by 2.17 based on the Bristol stool scale (16)
Hanevik et al., 2011	18 (11:7)	RCT	History of giardiasis 2 years prior and Rome II criteria	- Mesalazine	6 weeks	- no significant change in symptoms following mesalazine treatment	Low
				- 6 weeks			The study was a pilot study with small sample. It is unclear as to how to randomization and allocation concealment were conducted
				- 800 mg
				- BID
Tuteja et al., 2012	20 (10:10)	RCT	Onset of IBS symptoms in previously asymptomatic individuals after acute gastroenteritis characterized by two or more of: diarrhea, vomiting, fever, as reported by the patient	- Mesalamine	12 weeks	- no significant change in symptoms following mesalazine treatment	Low
				- 12 weeks			Insufficient sample size
				- 1.6 g
				- BID
Dizdar et al., 2007	34 (15:39)	RCT	Persisting abdominal symptoms 12 months after Giardia infection and Rome II criteria, as reported by Giardia outpatient clinic	- Ondansetron	2 days	- no significant improvement in symptoms after ondansetron treatment - Significant improvement in post-prandial nausea score before vs after ondanestron treatment (27.47 ± 21.89 vs 41.40 ± 23.04)	Moderate
				- 2 days			Small sample size
				- 8 mg
				- QD
Dunlop et al., 2003	34 (20:14)	RCT	New bowel symptoms in a previously asymptomatic individuals immediately after an acute illness characterized by two or more of: diarrhea, fever, vomiting, positive stool culture, as recorded by the patient or gastroenterology clinic	- Prednisone	21 days	- No improvement in abdominal pain, diarrhea, frequency or urgency based on a gastrointestinal symptom rating scale	Moderate
				- 21 days			Small sample size
				- 30 mg
				- QD
Menon et al., 2011	25 (15:10)	Retrospective	History of an acute gastroenteritis precipitating chronic diarrhea, as reported in clinic notes and hospital database	- Cholestyramine	Variable (1–15 years)	- decrease in diarrhea frequency of 5.9 stools/day	Low
				- 1–15 years			Retrospective study that only included people with bile acid malabsorption and infectious gastroenteritis.
				- 8.22 g
				- QD
Niaz et al., 1997	16 (16:0)	Retrospective	History of an acute gastroenteritis precipitating chronic diarrhea defined as distinct change in bowel habit with 4–15 loose watery motions per day as reported by the patient	- Cholestyramine	2 weeks	- decreased stool frequency of 5.1 stools/day	Low
				- 2 weeks			Retrospective study that only included people with bile acid malabsorption and infectious gastroenteritis.
				- 2–16 g
				- QD
Thakur et al., 2009	76 (17:59)	RCT	Rome II criteria and history of gastroenteritis or dysentery as reported by the patient	-Metronidazole	7 days	- improvement in pain, stool and total symptom scores at days 7 and 28	Low
							Study was not randomized, and both patient and physician were not blinded. 9 patients were lost to follow-up but it is unclear if they were included in analysis.
				- 4 weeks
				- 400 mg
				- TID
						- stool symptoms continued to improve between day 7 and 28 even though patients were no longer taking the medication
Lifshitz et al., 1990	29 (10:19)	RCT	History of chronic diarrhea after an episode of gastroenteritis lasting more than 3 weeks as reported by Pediatric Gastroenterology unit	- Pregestimil	variable	- 9 out of 10 infants had improved clinical symptoms, shorter time to improvement	Moderate
				- 3 – 7 days			Population was limited to infants with lactose intolerance. Inclusion was based on chronic diarrhea, not on established criteria such as Rome criteria.
				- 1500 mL/kg
				- Daily to provide 70 kcal/kg