Hello fellow sufferers,
A snippet of info that was given me by a pharmacist: The body becomes less responsive to antihistamine medicines with prolonged use. Its best to change occasionally.
Also I found that my allergies to grass pollens extended to cereal foods. I had asthma attacks etc. Then I tried a low carb weight loss diet. The improvement was incredible. I still consume cereal foods but much less now.
Beer also instigates an attack. However I have an antihistamine before I party now and no problems.
Cheers