seriousperson

Just elaborating on what was said above:
Use a "fragrance free" liquid laundry detergent and give everything an extra rinse.
Use a "fragrane free" soap on your body as well.
No knee socks for you for a while--at least until you've conquered the itch. I don't know what climate you're facing, but loose clothing would be better.
If you must where knee socks: No wool.
And maybe even triple-rinse them when laundering.
And definitely no perfume (of course). And definitely don't use anything other than the unscented soap if/when shaving your legs.
And only unscented moisterizing lotions.
Ditto on using the hydrocortisone cream or lotion.
If you are prone to skin infections, use some anti-biotic ointment on the lesions.

Be sure to launder your sheets in the same manner as above.
And if/when it clears up, if you have a flare-up, give your "fragrance free" products the sniff test.
I was going nuts about a year and a half ago--itching everytime I got in bed at night-- until my college-age daughter asked me what I was using to launder my sheets.
Upon investigation, I discovered that the alleged "fragrance free" detergent I had successfully used for a number of years was scented. So was the box of "f.f." Bounce sheets. I switched to a different brand of unscented detergent, and didn't use the anti-static sheets in the dryer for about a year. I think sometimes they just get the wrong ones in the right containers.