Table 1.

Probiotics and their function.

Probiotics	Function
Bifidobacteria and Lactobacillaeae	Tolerant to morphine, and probiotics containing these bacterial communities can prevent the development of analgesic tolerance in the morphine-treated rats [66].
B. longum and L. rhamnosus	Maintain a healthy intestinal barrier [68] bacterial translocation, and neuroinflammation by manipulating the gut microbiome [69].
Lactobacillus genus	In mice, it was shown to induce opioid and cannabinoid CB2 receptor expression and mediate analgesic activities in intestinal epithelial cells [70].