hi i had gone through your query and understand your concerns. i would come up with the possibility of 
ALLERGY is the underlying cause for your sufferings.
the possible causes of allergy include,
-inherited influences,
-insect bites
--food and food additives
-physical factors like heat,
cold,sun,exertion,pressure,vibrations.
-emotional stress
-internal diseases
-intestinal worms are some possible causes.
treatment option;
-without trating the underlying cause your 
hives cant be cured. for this condition,
i advise you taking   
Homeopathic medicines gives  safe and permanent  cure for your complaints 
consult your local homeopathic physician for correct diagnosis of the case and remedy to fit your complaints 
I hope this is helpful for you, thank you