Thanks for the query,
Probably you are suffering from urticaria
It is characterised by red raised itchy rashes on body.
It is a type of allergic reaction
You may require treatment with oral anti histamines
Topical steroids will also give some relief.
Please meet a dermatologist
for exact treatment.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.