which antihistamine to use for allergies??

i use benedryl.... but it make my dog really tired and sleepy... i wanted to try cetrizine.... would that be ok??

My vet said Piriton is what I should use so I wouldn't like to say yes or no.

Dipansaluja - I note you are in the USA...
I would like to point out that the Benadryl sold in the USA is a different drug to that sold under the Benadryl name in the UK.

Benadryl USA is diphenhydramine which can cause sedation. In the UK, diphenhydramine is sold as a sleep-aid called Nytol.

Benadryl UK is acrivastine, a non-sedating antihistamine.

Cetirizine is sold as Zirtek in the UK.
Piriton is a drug called chlorphenamine maleate.