Another Question Allergy Tablet Advice

My pups almost 6 month and i'm wondering what allergy tablet i could give him to see if it helps with the small bumps on his body, I've tried 3 chemists and none of them to piritin, So i'm going to asda later to do shopping, Would other would be ok to use? They do :
Zirtek
Piriteze
Benadryl
Asda Own Brand
Galpharm

And how much would i give him for his age? Sorry for all questions i've posted lately

Go for the Asda own brand, this the one I use for Rocky at the top of the thread below. Just give half a tablet, Piriteeze is something else, do not give to your dog.

https://staffy-bull-terrier.niceboard.com/t19301-sticky-allergy-advice?highlight=allergy+advice+sticky