What causes poison ivy rash?
Exposure to the resin of poison ivy leaves, stems, branches, and roots causes an allergic reaction in some people. The very first time an individual is exposed to poison ivy, they may or may not develop a rash. Some people are genetically programmed not to develop a rash from poison ivy. If you are predisposed to developing a rash from poison ivy, the rash usually appears between 10 and 14 days after your first exposure to the plant. A second exposure may cause a rash to develop within 2 to 3 days after exposure.
Dr. Lowell Goldsmith and Dr. Jeff Bernhard contributed their expertise on behalf of VisualDx for the above information.