If you have sensitive or reactive skin, it's important to introduce any new product gradually. First, perform a patch test: dissolve a small amount (about a teaspoon) in a cup of warm water. Soak a cotton pad in the solution and apply it to a small area on your inner forearm. Leave it for 10-15 minutes, then rinse. Monitor the area for 24 hours for any signs of redness, itching, or irritation. If no reaction occurs, you can proceed to use it in a bath. For your first full bath, use half the suggested amount (e.g., one small handful). Limit your soak time to 10 minutes. Observe how your skin feels during and after. The product description advises avoiding use on irritated skin and discontinuing if any discomfort appears. If your skin tolerates it well, you can gradually use the standard amount. This cautious approach helps you understand your personal tolerance to the marine salt and the fragrance.