The picture above shows the classic linear pattern of blisters that you can get after having contact with poison ivy, poison oak, or poison sumac.
Poison Oak Rash Picture Poison Ivy Pictures
By Vincent Iannelli, M.D., About.com Guide
Updated May 17, 2006
About.com Health's Disease and Condition content is reviewed by the Medical Review Board
The blistering rash that you can get after having contact with poison oak.
Poison Oak Rash
CDC
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