Itchy skin without any rash can be due to dry skin, thyroid causes, diabetes and iron deficiency anemia. However other causes like dry skin (xerosis) due to hot or cold weather with low humidity levels, long-term use of air conditioning or central heating, and washing or bathing too much can also cause itchy skin. Apart from that, you can have itchy skin due to irritation and allergic reactions to chemicals,wool,soaps,cosmetics and certain foods, neurodermatitis, thryoid and liver conditions as well.
Get your liver function tests and HB levels done to completely rule out iron deficiency anemia. Oral antihistamine, such as Benadryl can also be used but may cause drowsiness. You should take a comfortably cool bath and wear smooth-textured cotton clothing.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.