Sophie is now 5 1/2 months old. She's matured in so many ways thank god and has turned into a loveable yet stubborn but mostly behaved dog (due to my lack of appropriate training I'm sure!), but we are still working on her every day. About 3-4 weeks ago she started losing the tiny teeth in the front of her mouth (incisors) and her new adult teeth have grown in there nicely. I never found any of them so I assumed she swallowed them. She looked funny with missing teeth for a little while. Reminded me of a toddler. The last 2 weeks, she's been chewing a LOT, and whining, and I've found lots of blood on several of her toys and her antler. She lost SEVERAL of her premolars - they were quite large, and I found most of them on the carpet. One had a really long root looking sharp thing on the end and it was VERY loose for an entire day and bleeding badly but the vet made me promise not to try and pull it out and just give her some soft chew toys. A frozen wet rope toy did the trick. She's chewing a lot, and getting into a bit more trouble with her mouth on furniture (which I had broken that habit weeks ago) but it seems now she wants to put her teeth on whatever she can find when it hurts. Sometimes even me but she doesn't bite hard and as soon as her mouth is on me, she has a moment where she realizes that she shouldn't be doing it and stops. I'll be glad when puppyhood is over. On top of teething she contracted giardia again (second time) - not sure from where since now that she's vaccinated I take her to the lake now, on neighborhood walks (and my area is FULL of dogs) and she goes to day care. The vet assured me that it's just puppyhood and I should see less of this when she's older. I asked about pro-biotics and also maybe an immune system booster. She told me nothing for immune system available really works, but said a pro biotic might not be a bad thing. Is anyone in the US giving your dog a probiotic and if so, can you let me know the name and if you feel it's working?