I was using pressed wood pellets (no cedar in mix) for my one ferret who only used her box periodically. It was recommended by a friend with over 10 ferrets because it worked well and was inexpensive. I didn't find it to absorb better than the pressed paper pellets. Then I got a second ferret (who was much more willing to use the litter box!). Suddenly my first ferret was waking up with horrible coughing and wheezy breaths. I went to the vet, tried cold and allergy medications, etc. The problem couldn't be solved! It was horrible listening to my little baby having so much trouble. Finally I realized that when the wood pellets were actually used (by my newest fuzzy) they would break down into a sawdust type of material under the litter. I took out all the litter and within a few days my original baby was back to her healthy self! My friend with the 10+ ferrets said some of hers cough also when waking up (although she doesn't think its caused by the litter). I will never know if that is what caused all this trouble, but I will never try it again! We are now happily and safely using Swheat Scoop. A safe and scoopable litter. The only drawback is that a little is scattered by my baby - I can deal with that! [RI] [Posted in FML issue 3127]