Hello, Welcome to healthcare magic,
You seem to be having a condition called as chronic urticaria
In about 90% of the cases, it is not possible to find out a cause for the urticaria, which is when we call it is “idiopathic”.
In only about 10% of the cases, it could be due to a specific food, medications and infections, or auto-immune.
It is unlikely to be due to minoxidil
as the hives are coming not on the scalp
but all over the body and you are applying it and not taking internally. Are you taking any kind of over the counter medications especially pain killers or dietary supplements, Ayurvedic concoctions, herbal remedies, etc? If so, try to see if it correlates with onset of rashes?
Do you have a bad tooth (caries) which troubles you on and off which you seem to ignore? If so, please get it treated as many times, the source of infection triggering the rashes could be a tooth infection
I would also suggest you to get your thyroid
profile checked as urticaria could co- exist with a thyroid abnormality. And sometimes, correcting the thyroid status would control the rashes to some extent.
Have you noticed that the rashes triggered by cold air (eg AC), sweat (eg, after a workout) or water (eg, after a shower). These are well known triggering factors.
But unfortunately, most of the patients fit into the idiopathic category.
I would suggest you the following –
1. Do go through the above checklist as you might pick up a clue to a triggering factor and try to exclude it.
2. You could continue taking cetrizine
daily or every alternate day after consulting with your doctor.
3. Avoid foods containing preservatives ( eg , canned food, colas , etc) and those containing food colourants( eg, kebabs at restaurants which have orange colour) as they are potent allergens.
4. Keep a food diary and write down everything you eat on the day you get rashes. You can look for any common food, which repeats in the diary, eliminate it and see if it helps.
Unfortunately, it is not possible to say when your allergy
will be “cured". It depends from person to person. Play Sherlock Holmes and try to find the cause.
Hope this helped you.