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Photo of rash from a ragweed plant
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Ragweed plants typically bloom in the United States in the fall. Ragweed pollen is a primary cause of hay fever (allergic rhinitis).

For those who are allergic to ragweed, exposure to the plant pollen through touch or airborne contact can also cause a rash. You might notice itchy red streaks on the skin or swelling of the eyelids. A ragweed rash usually develops within two days of exposure and resolves on its own within three weeks, as long as you avoid additional ragweed exposure.

In the meantime, control itching with an over-the-counter anti-itch cream, such as hydrocortisone cream, and an over-the-counter antihistamine if needed. Talk to your doctor if the rash is painful or lasts longer than three weeks.

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See more Multimedia June 25, 2020