Oregano oil is a common choice for SIBO thanks to carvacrol, but form matters....

https://www.4shared.com/office/gu7C2Q5cge/pdf-78857-27675.html

Oregano oil is a common choice for SIBO thanks to carvacrol, but form matters. Many prefer capsules over liquid to avoid the potent taste. If you are working with a practitioner, a 2 to 4 week window is a typical timeframe to assess your comfort.