poison ivy

You can try taking Benedryl allergy capsules. I take 2 at bedtime to control the itching but only 1 at a time during the day because they can make you drowzy. The antihistamine in Benedryl should help relieve the itching but you will also need something topical. The BandAid anti itch gel seems to work for me. Also washing with Burts Bees Poison Ivy soap helps. It helps more if you wash when you are first exposed (use cool water) but I find it helps to wash the itchy, rashy areas with it. It seems to have a drying effect, especially if any of it is oozing. OTC hydrocortisones are also helpful.

If you are three weeks into it and it is still spreading, you probably should see a doctor for a prescription cortisone treatment.