Table 3.

Summary of key effects of acid suppressing agents in relation to multiple sclerosis

Agent	Response
H2R antagonists	No reports of acute worsening of MS disease status Increases EAE incidence Promotes Th1 and Th17 responses Promotes production of proinflammatory cytokines Promotes T cell response, for example, proliferation Promotes suppression of Th2 response Block suppression of dendritic cells
PPIs	No reports of acute worsening of MS disease status Not studied in EAE Suppresses reactive oxygen species Lessens expression of adhesion molecules Suppresses production of proinflammatory cytokines
Increased gastric pH (H2R antagonists, PPIs, or antacids)	No reports of acute worsening of MS disease status Possibly alters microflora in the stomach and small intestine Possibly alters neutrophil response Can lead to vitamin B12 deficiency

EAE: experimental autoimmune encephalomyelitis; H2R: histamine receptor-2; MS: multiple sclerosis; PPI: proton pump inhibitor; Th: T helper cell.