In the Middle East yoghurt is routinely used for intestinal problems (unsweetened and with live organisms). It is also helpful for Candida albicans. It cannot cure a serious ailment, such as ulcerative colitis, but is a very useful adjunct. I lived and worked in the area for a couple of decades and from what I have observed, and myself experienced, I give it my vote. Goat or sheep milk is often used. Personally I know of no side effects.
Hi there!
Probiotics is one of the newer concepts in the market and little long-term research is available though these are unlikely to have severe side effects. I personally would not like to withhold probiotics as long as they are tolerated well. Though apathy is not one of the regular side effects, one may stop these for the time being and get tested for nutritional deficiencies in case it might be involved. If no other cause of the symptoms is diagnosed one may completely withdraw the probiotics and see if that seems to help.
Hope this is useful.
Take care!