Table 2. Data of relevant studies extracted on search using appropriate keywords.

Keywords	Data collection
1-Helicobacter pylori gastritis and depression.	10
2-Depression and stomach.	12
3- Helicobacter pylori infection and serotonin.	0
4- Depression and dyspepsia.	19
5-Dyspepsia and serotonin.	0
6- Anxiety and stomach.	45
7-Anxiety and dyspepsia.	32
8-Helicobacter pylori and Tricyclic antidepressants (T.C.As).	0
9-Helicobacter pylori and Monoamine oxidase inhibitors(M.A.O.Is).	0
10- Stomach and brain axis	9