I have intchy skin.from head to toe.what really might be the problem the cause.allergex pills don't work.

It could be food, medication, contact (wool, something similar), an illness, some sort of insect.

Have you asked a Physician?

I too have itchy skin, but I know why:
I have had dry skin my whole life (I'm now 66).
Right now mine itches more because it's winter. I have various ways to deal with winter dryness, including a little desktop humidifier that I made myself, unscented soap which I use sparingly on just parts of my body that really need it (and minimal showers if possible), unscented laundry detergent using the minimal amount and rinsing well, and wearing a layer of silk knit next to my skin, under other layers of polar fleece, no wool.
In the summer I itch because I seem to be allergic to my own sweat. So I have to wash when I sweat. My scalp has a tough time too.
I stay away from lotions except on my hands and face.

OH, and hydrate! Drink tons. It really does work.