How much salt to put make saline water for gargling?

For a saltwater gargle, you'll need to dissolve about half a teaspoon (2.5 grams) of salt in a cup (240 milliliters) of warm water. It's important not to use too much salt, as it can irritate your mouth and throat. If the water is too salty, it can also draw water out of your cells, which can lead to dehydration.