Maltese behavior

Question
We have a Maltese that is about 4 months old (had her since she was 8 weeks).  The dog is always eating her poop and our westies poop. The vet gave us some stuff to sprinkle on the poop which worked for a while but does not seem to work anymore.  Is there anyway we can get her to stop eating poop?

Answer
HMmmm this is so odd have the vets said why she is actually eating the poop and what is attracting her to it?
I think you can buy some sort of charcoal additions to food that makes the poop taste odd !
but i would look at this site it has great ideas of what causes the behaviour
http://www.petlibrary.co.uk/dog-care/why-do-dogs-eact-poop.html
please let me know if this helps.
Good luck.