The vet told me to give Bella 1/4 of a baby aspirin after she had a mild reaction to her last vaccine.
I am also shocked at the order the email put the drugs in!! And ANY drug is toxic if you give too much of it....that should go without saying! You should know the appropriate dosage for your dog, just like you should know the appropriate dose for yourself or your children, BEFORE giving it!!
This may be something that some don't know:
If you're unsure about a dosage or what medication to use, you can always call an Emergency Vet (if it's after hours or the weekend and you can't get ahold of your vet, that is). When Bella was little she had so much anxiety about being alone for even 1 min (I'm pretty sure the breeder let her daughter sleep with her

) so we had heard that you could give Children's Benadryl (liquid) to calm her down some. I had no idea how much to use, and when I searched it on the internet, they were giving the dosage to me in mg instead of mL. So, I called the Emergency Vet and explained that I hadn't ever been there and this wasn't really an emergency, I just wanted to check dosage so I wouldn't overdose my tiny puppy. The woman put me on the phone with a vet tech who got out a book and looked the appropriate dosage amount up for me! My thinking was, Vets care about animals, and surely if they can do something as trivial as tell you an appropriate dosage amount in order to make your pet more comfortable and keep their human from overdosing them, they would!
Obviously, if your dog is on other drugs (even herbal supplements), it's just as important to tell their vet as it is for you to tell your doctor all the meds you are taking--meds, even herbal supplements, DO interact sometimes.