--- title: I have chronic constipation, do I need to fast for longer than 12 hours for the small intestinal bacterial overgrowth (SIBO) test? description: No, but we do recommend following the restricted diet for 36 hours before the test. --- [Skip to content](https://helpcentre.healthpath.com/en/knowledge/i-have-chronic-constipation-do-i-need-to-fast-for-longer-than-12-hours-for-the-sibo-test#main-content) English Show submenu for translations ![HP-logo-414-1.png\]](https://helpcentre.healthpath.com/hs-fs/hubfs/HP-logo-414-1.png?height=40&name=HP-logo-414-1.png) - [Default HubSpot Blog](https://healthpath-1.hubspotpagebuilder.com/blog) Open main navigation Close main navigation - [Default HubSpot Blog](https://healthpath-1.hubspotpagebuilder.com/blog) - English Show submenu for translations - [Go to healthpath.com](https://healthpath.com/) [Go to healthpath.com](https://healthpath.com/) Hello. How can we help? - There are no suggestions because the search field is empty. 1. 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