I second Jeff's comment. Acetominophen is just plain poisonous to ferrets. And while they can generally tolerate aspirin, dosages MUST be determined by a vet and carefully monitored. In a study involving ferret toxicology from 1982: http://www.pnas.org/content/79/23/7557.full.pdf it was found that too much aspirin causes a buildup of ammonia in the blood, which can easily be fatal for ferrets. And ferrets that are deficient in arginine should NEVER be given aspirin. At all. In any amount. Arginine-deficient ferrets cannot tolerate aspirin. It kills them. (Arginine is an amino acid that ferrets usually get from bird meat in their diet, but it can also come from vitamins. If the ferret has been on a poor diet it should not get aspirin. Period.) Lesson: just as Jeff said. Don't give your ferret meds unless your vet prescribes them, or you have done genuine, proper, diligent research (or both), and you know EXACTLY what you are doing. Don't guess. I once had to give mine some decongestant for nasal symptoms due to flu. (And man, was I miserable having to watch the little guy go through the same flu that I'd had, despite my earnest attempts to avoid passing it on.) It was surprisingly difficult to measure a proper dose, even knowing in advance what it was, because it was so small. Calculating proper dose by body weight is tricky business, and you can't just use humans for comparison, because different animals tolerate different medications... differently. For example: you can often give a dog enough morphine to kill several humans, and it might get a bit sleepy, or might just snarl at you for giving it an injection. Give the same amount to a cat, and it will probably become hyperactive and go into stimulant-induced convulsions (much like those caused by strychnine) before it dies. If you think I'm trying to scare you, you're quite right. If you're giving your pet "guesswork" medications, be afraid. Be very afraid. And even if the meds are from a vet, unless the vet says no (you should ask), if you're giving meds it is probably a good idea to make sure they are getting vitamins too. Just in case. Lonny Eachus [Posted in FML 7459]