These reports are in humans and are breaking info, so not done on a veterinary basis, yet, but may point to cautions. In humans it is turning out that multiple users of a few types of HIGH DOSE probiotics have been having complications for unknown reasons according to http://www.consumerlab.com/ in two sequential monthly reports, with increased reporting of such problems noted in the second newsletter. CL members may find this URL useful IF I trimmed it right though it does NOT discuss this problem. Non-members will likely not have access: https://www.consumerlab.com/reviews/Probiotic_Supplements_Lactobacillus_acidophilus_Bifidobacterium/probiotics/ I do not know how to trim the access URL for the most recent article to get CL members directly there so link from your most recent CL newsletter. Eosinophilic Syndrome is being seen and so are allergies, problems apparently not see with the lower dose probiotics. Some of those affected by the autoimmune disorder after taking high dose probiotics are having what appears to be permanent motor and sensory deficits in the extremities even after hospitalization and longterm treatment. When puppies get a correct dose their immune systems are stimulated, so perhaps a similar things happens but far too greatly when the immune disorders occur after high doses: http://jn.nutrition.org/content/133/4/1158.abstract Similar topic: http://www.ncbi.nlm.nih.gov/pubmed/20803023 So, it is NOT that probiotics are bad, but that OVERDOING THEM CAN BE BAD. Since many people give ferrets probiotics and their sizes are small with dosing a bit of guessing game I suggest that anyone using probiotics w ferrets check first with your veterinarians. That is ALWAYS a good thing to do, but in this case it may be even more important. A search in PubMed finds this report associated with the first cases that were noted and then I think it was only brand but since has broadened to other high dose ones after reading the CL report: QUOTE Case Report Rheumatol. 2012;2012:934324. doi: 10.1155/2012/934324. Epub 2012 Dec 6. Severe eosinophilic syndrome associated with the use of probiotic supplements: a new entity? Mendoza FA, Purohit S, Kenyon L, Jimenez SA. Source Jefferson Institute of Molecular Medicine and Scleroderma Center, Thomas Jefferson University, Philadelphia, PA 19107, USA ; Rheumatology Division, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA. Abstract Severe eosinophilic syndromes related to the administration or use of unsuspected immunogenic substances have been described previously. Many of these diseases presented initially as clusters or isolated cases. The spanish toxic oil syndrome, the eosinophilia myalgia syndrome, and nephrogenic systemic fibrosis are examples of such diseases. We describe 2 cases of a severe eosinophilic syndrome characterized by marked peripheral blood eosinophilia (>15,000cells/ml), mononeuritis multiplex, and necrotizing vasculitis which developed in a close temporal association with the recent onset use of nonprescription probiotics. There was no history of a prior autoimmune disease. Although both cases had prompt response to immunosuppression with rapid resolution of peripheral blood eosinophilia and accompanying constitutional symptoms, they remained with permanent neurological deficits. PMID: 23259129 [PubMed] PMCID: PMC3521401 Free PMC Article END QUOTE Full article for free: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3521401/ or http://www.hindawi.com/crim/rheumatology/2012/934324/ Sukie (not a vet) Ferrets make the world a game. Recommended ferret health links: http://pets.groups.yahoo.com/group/ferrethealth/ http://ferrethealth.org/archive/ http://www.miamiferret.org/ http://www.ferrethealth.msu.edu/ http://www.ferretcongress.org/ http://www.trifl.org/index.shtml http://homepage.mac.com/sukie/sukiesferretlinks.html all ferret topics: http://listserv.ferretmailinglist.org/archives/ferret-search.html "All hail the procrastinators for they shall rule the world tomorrow." (2010, Steve Crandall) A nation is as free as the least within it. [Posted in FML 7686]