I'm not your vet (no surprise there), but couldn't Pax's infestation have been more sever--he was symptomatic give or take a month, before Pilot.
In the alternative, is there *any* downside to the IBS treatment protocol? From the earlier linked PetMD article,
"Outpatient medical management is the most common method of treatment for irritable bowel syndrome. It is highly recommended that dogs that have been diagnosed with irritable bowel syndrome be fed a diet that is highly digestible and has a high volume of fiber in order to help restore and maintain the normal bodily function of the digestive tract. If there are signs of highly stressful elements within your dog's environment, it is also recommended that you make attempts to remove these elements." |