Good evening ma'am, I suggest you to observe when does this itch occur, meaning after having what food or after breathing particular smells like perfumes/floor cleaning agents/paints, sometimes it can occur even due to dust mites etc....
What you are suffering with is Allergy which you might have already understood by now. I advise you to find out is the cause, to what allergen are you getting these reactions.
If you are able to find the cause, eliminate it from your home.
In the meanwhile continue Citrizen, Allegra.
You can consult ENT Specialist for a revised medication.
If you still can't find the cause, then it is advisable to get a Skin-prick Test to find the allergen.
Next Steps
Find the cause. Eliminate it. Use medications in the meanwhile.