Pharmacognosy is the study of the medicinal uses of natural compounds. The qualifications of people who offer advice in natural medicine vary through the complete gamut from those who do not take risk factors into account (usually because they innocently have not done their homework well enough, but sometimes because they choose not to) all the way to those with advanced degrees. BUT the degrees can vary, too. There is at least one rumor mill offering titles based on little to no real knowledge or experience, while at the same time there are graduate programs in pharmacognosy at the pharmacology departments of some very respected, accredited universities. Okay: licorice root -- very natural and, hey, it is used as a flavoring for some candies (though many now use artificial licorice flavoring or use anise which does not carry the risks of licorice) so you would figure it is safe. Right? Nope. It is known to be potentially very dangerous for humans and from hearing of too many ferrets beating the odds in a bad way for problems like throwing clots (thromboses) or having a shortened lifespan with cardiac problems I am not personally inclined to consider it safe for ferrets, though I will be frank and say that I have not to date found actual REAL research into ferrets and licorice root even checking in places like Pubmed. Still, the effects are of such a basic nature that it is far better to be safe than to be very sorry. Licorice, Glycyrrhiza was studied carefully for treating ulcers during WWII by a Dutch physician, F.E. Revers who found that it did help the ulcers BUT EVEN IN THAT SHORT TRIAL 20% OF THE PATIENTS DEVELOPED EDEMA, a very scary sign which fortunately stopped when the licorice was stopped. Since then a great many studies have shown the dangerous effects licorice can have on the heart, headache, etc. Dr. Varro Tyler, Distinguished Professor Emeritus of Pharmacognosy at Purdue University is also past president of the following four respected associations: The American Society of Pharmacognosy (1st president), the American Association of the Colleges of Pharmacy, the American Council on Pharmaceutical Education, and the American Institute of the History of Pharmacy. On licorice he notes: "These undesirable effects are mineralcorticoid in nature. Specifically, they include headache, lethargy, sodium and water retention (the edema noted by Revers), excessive excretion of potassium, and high blood pressure. Eventually, heart failure or cardiac arrest may result." (It is interesting to notice that is it increased hydrocortizone levels. I will have to check back through some past vet posts, but wasn't there a postulated possible negative effect on the pancreas of ferrets (I seem to maybe recall a hypothesis for a diabetes -- a rare problem in ferrerts -- connection.). I'll have to check later, or if someone else feels like doing so -- check in past FHL vet posts since I think that may where I either read it or read something I am mixing up with it .) Another Varro Tyler text refers to licorice mimicing excessive secretion of the adrenal cortex hormone aldosterone to the point in humans where is can cause pseudoaldersteronism. It would be interesting to know if giving herbal compounds contain licorice has thrown off diagnoses of adrenal disease in some ferrets. Among humans the German Commission E approved the use of licorice in humans who have ulcers BUT only for a very limited time and at low doses and lists a wide range of people who should not use it even with those precautions (including those with heart disease, those who are elderly, those who have liver or kidney problems, those who are already low in potassium, etc.). The appropriate PDR notes some other uses but also with strict cautions. This is an easily abused, powerful herb which can pack some high risk factors. [Posted in FML issue 4849]