If you rub epsom salt into your hair, this is the effect

pre-shampoo rinse that may help loosen dry flakes so they wash away more easily.

Stir 2 tablespoons of Epsom salt into 1 cup of warm water until mostly dissolved, then slowly pour it over the scalp before shampooing. Let it sit for 2 to 3 minutes, massage lightly, and then shampoo as usual. If flakes are persistent, worsening, or paired with redness or hair loss, that’s a good moment to check with a dermatologist instead of trying to tough it out.

Cup of dissolved epsom salt solution beside a shampoo