Poison oak

Typically 1 to 3 weeks, depending on how much skin is affected and how quickly treatment is started — earlier treatment generally shortens the course. Most cases resolve completely without any lasting marks once the rash has cleared. This timeline holds true whether or not you use a prescription treatment.

The rash itself isn't contagious, but the oil (urushiol) can spread to other people or surfaces if it's still present on skin or clothing. Washing exposed skin and clothing promptly after contact can help prevent this. This is a common misconception that leads people to avoid others unnecessarily.

They cause the same type of reaction from the same oil, just from different plants — treatment is the same either way. Both cause the same allergic skin reaction and are managed with the exact same treatment approach. Learning to identify the specific plant in your area can help you avoid future exposure.

Cool compresses, over-the-counter anti-itch creams like hydrocortisone, and avoiding scratching can help manage mild cases and reduce the risk of skin infection. Taking an oatmeal bath can also help soothe widespread itching and irritation. Calamine lotion is another over-the-counter option that many people find soothing.

Topical steroids can cause skin thinning with prolonged use; oral steroids (for severe cases) carry their own considerations your clinician will review. Your clinician will choose the option that best fits how widespread your rash is.