From Homestead Remedies, 1900: “For the rash that develops from poison ivy, boil oatmeal in water until it becomes pasty in consistency. When the paste is warm enough to be tolerated, apply to the affected area of skin. One or two tablespoons of baking soda can be added to the paste for relief of associated itching. An alternate remedy is to mix three teaspoons of baking soda with one teaspoon of water, apply it to the affected area and let it dry. These treatments are tried and tested, and will relieve scratching and itching quickly if treated with proper haste.”