Suggest Remedy For Skin Itchiness Every Night Before Sleeping

I am suffering of itchiness every night before I go to sleep. I used to take Metformin because my doctor told me that I am border line of type 2 diabetics. My doctor advise me to stop the metformin because it my cause the itchiness. I already stop the metformin but I am still itchy before I slept. We done everything s changing new bed, bedding, new carpet, new drapes. I called also an expert of all kinds of house bugs but found nothing. Also called the K-9 dogs found nothing. I see many allergies doctors but no cure. At present I am taking Zyrtec and prescription ointment.