[smartpuppiepets]

Hy,
You can safelly deworm them with "pyrantel" beginning at 2 weeks of age, and in fact you should have done it already with the litter and mom as well, every other week starting at 2 weeks old we give pyrantel. Ok, this only takes care of common worms and although it is pretty much protocol to deworm puppies and mom together anyways, it will not help you out with the gyardia, and the regular 3 days of Panacur also will not help you out with the gyardia , if that is the case and it is a possibility. In order to be effective against gyardia the trick is to give from 5 to 9 days (i give 9 days) consecutive at the same time every day. It will get rid of any gyardia plus any worms of tape worms that other dewormers like Pyrantel can't.
How i know that? Well... years of breeding and experience, and i had a puppy with similar simptoms as i told you ... it went like soap opera until a fecal exam did show the nasty gyardia. .
The recomended dose is at 1 gram per day and i have used that without any problems at all. your puppy is 14 ounces so he is almost 2 pounds at 5... weeks old, he is not a "teacup" sized ( not that i like the word but it serves the purpose) and is doing good on development i think. Would you mind telling me how big are the parents? If you to PM your number i can call you , i do not mind. Also is it your first litter? How long have you being breeding?
Deworming is not going to cause loss of appetite or anything. But keep in mind that if it something neurological it is not going to help either and probably symptoms will progress and things will take a different direction.
How is he doing today?