. Author manuscript; available in PMC: 2014 Apr 1.

Published in final edited form as: Curr Gastroenterol Rep. 2013 Apr;15(4):316. doi: 10.1007/s11894-013-0316-6

Table 1.

Phenotypes of PPI non-responders based on physiologic testing

	Phenotype 1	Phenotype 2	Phenotype 3	Phenotype 4
	Persistent acid reflux	Hypersensitive	Functional overlap with GERD	Functional heartburn
Acid esophageal exposure *off* PPI^*	+	+/−	+	−
Acid esophageal exposure on PPI^*	+	−	−	−
Excessive number of reflux events with impedance on PPI	+/−	+/−	+	−
Positive reflux- symptom association with impedance on PPI	+/−	+	−	−

prolonged wireless pH monitoring both off and on PPI may be used to evaluate esophageal acid exposure in a single examination ⁸