No. Centrine is generally a prescription medication. You might be able to get it w/o presciption from an online pharmacy such as Internetvets.com When I had a vet give some to a kitty of mine who was vomiting and had horrendous diarrhea, I looked it up in their drug reference library, but can't remember whether or not they required a prescription. Another vet told me to be careful, that this drug can sometimes have an adverse reaction of stalling gut activity. I do not think it was intended to treat mild stomach upset or nausea. I think something like slippery elm or Pepcid would be safer for that.
Sally in San Jose
