Drug Interaction WarningsBrush Twice a Day to Relieve SensitivitySensodyne contains potassium nitrate, an ingredient clinically proven to reduce painful sensitivity. If you brush twice a day with Sensodyne, you should begin to feel relief within two weeks.Build Protection With Every UseBrushing twice a day with Sensodyne Builds a "shield of protection" against painful sensitivity. Unlike regular toothpaste"s, Sensodyne is specially formulated for individuals with sensitive teeth. And, since Sensodyne has fluoride, it helps protect against cavities too.Sensodyne...the #1 dentist recommended brand.