If the rash that you describe is red, itchy, has raised skin that you can feel, goes away after a few hours only for new ones to appear in their place, does not leave a mark or bruise, then this is acute urticaria
. That you have had it for >6 weeks, makes it chronic urticaria.
80% of people with urticaria do not have allergy, although a pre-existing allergy to (say) house dust mite, pollens or shrimp does not make it more likely for this type of urticaria to appear.
Infections, underlying thyroid problems, diabetes
, inflammation inside the body (can be several conditions, say endometriosis
) and stress makes these lesions appear and can last quite long.
The treatment (that you don't like) is the right one, long-acting non-sedating antihistamines like allegra 180mg once in the morning, and cetirizine
10mg at lunch time or evening for 6 weeks (max 3 months). Unless you continue on high dose antihistamines, this will recur.
If you think you may have a thyroid problem, get TSH fT4 and TPO antibodies
If there is a chance of an infection, please get this checked and treated as well.
I hope this helps.