All my patients with SIBO that is Methane positive.
An interesting study that shows Lactobacillus reuteri (DSM 17938) reduces methane production in functional constipation.
An interesting finding since Lactobacillus reuteri produces and antimicrobial property called reuterin that inhibits gram positive and gram negative bacteria. As we know gram positive and gram negative bacteria produce hydrogen which is the fuel source for Archaeal organisms (Methanobrevibacter smithii) that produce methane (CH4). Perhaps this intervention is reducing the archaeal food source.
I only know of one supplier of the (DSM 17938) strain and that is BioGaia.
If you know of any other supplements that contain DSM 17938 please post below. Or for all you clever patients of mine who love researching please do some googling and post your findings below.