Call and find out. It's important to have the correct dosage. If he's still growing vet may want to have a current weight before prescribing more. My vet allows me to go in and have the dog weighed and chart updated without an appointment or charge.
It might vary from vet to vet. We don't need to make an appointment at our vet. I just go in and buy more when we need it.do I need to make an appointment and take my dog in to get more or can I just stop in?