Why Scratching Itches Worsens Rashes but Fights Bacteria

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Why does scratching an itch make your skin feel worse afterwards?

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These quarter-inch workers build five-foot-tall mounds containing between 30,000 to 16 million insects - the largest above-ground ant colonies.

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Led by Dr. Daniel Kaplan, the team studied mice with skin rashes to uncover the effects of scratching.

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Mice that scratched had more swelling and inflammation compared to those that couldn’t. The culprit? Pain-sensing neurons which release "substance P," which activates immune cells.

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This causes a chain reaction, worsening the redness and swelling of the skin.

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But here's the twist — scratching lowered bacteria levels of Staphylococcus aureus. This bacteria is responsible for most skin infections

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However, the harm scratching causes outweighs its benefits for chronic conditions.

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Dr. Kaplan's team is working on therapies that target mast cell receptors to reduce inflammation.

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Until new treatments arrive, resist the itch — scratching may not be worth the risk.

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