Hi Lance - There is a lot of research that indicates probiotics are important and do work to balance out GI harmony but appropriate testing is an underlying factor that goes along with a treatment protocol.
Antibiotics are well known to cause GI bacteria disruption (both good and bad) and often, testing isn't done to make sure that the good bacteria are replenished after a/b treatment. Many times, leaky gut syndrome or intestinal permeability is present and goes undetected which eventually causes a variety of symptoms including autoimmune responses and often this is caused by antibiotic use that is not balanced out with testing and adding back the specific, appropriate probiotics that keep the intestinal mucosa functioning optimally. The doctors who have advanced education in functional medicine are typically very aware of the specific tests to help maintain and/or regain a healthy gut bacteria environment. It's well acknowledged that most GI doctors don't have a clue.
Jackie