i rescued a jack russel with chronic flea allergy.i tried alsorts.unfortunately most flea preparations work by the fleas being killed after they’ve bitten. it’s the bite the dogs are allergic to. nothing really helped as he was super-sensative. when i got him over onto a natural diet [raw meat, vegetables and hard-baked wholemeal bread] his immune system clicked in [from his body coping with bacteria in raw meat] and he never had a flea allergy again in the last 10 years of his life, despite moving out of town where we have a garden full of wildlife and associated fleas!

Need to know what type and brand would be best