I recently Bella had her annual exam and my vet said as long as she is on Heartworm medication for the past year and I purchase it through him than he only needs to do the Heartworm test every other year.
However, if I purchase the medication from another vendor than he make me repeat the test yearly.
I think this is just a way for him to get more money by me purchasing meds via him but he has reasonable costs so I am ok with it.
__________________  Ashley mom to Thumper  and Bella  RIP Boomer |