Thanks for query on HCM.
Itchy hives all over body indicate some
allergic reaction also called
urticaria.
It is usually allergic so,be watchful for any triggering factor.
It might be due to exposure to certain chemical,irritant,perfumes,after some food,
using any body lotion,soap,after insect bite and even after excessive exposure to sunlight.
It's often impossible to find out exactly why hives have formed.
Apply cool compresses or wet cloths to the affected areas,apply calamine,aloevera lotion for cool effect,try to work and sleep in a cool room,Wear loose-fitting lightweight clothes.
Take tablet levocetrize or
fexofenadine to subside allergic outbreaks.
Consult dermatologist for proper diagnosis and medical management.