Whitening your teeth should not be painful, but some people may experience temporary sensitivity or discomfort during or after the procedure. This is typically caused by the whitening agent penetrating the tooth enamel and irritating the nerves in the teeth. However, most professional teeth whitening treatments use a specialized gel that contains a desensitizing agent to help minimize discomfort. Your dentist may also recommend using a toothpaste designed for sensitive teeth in the days leading up to and following the whitening procedure. If you do experience discomfort or sensitivity, it is important to notify your dentist or dental hygienist so that they can adjust the treatment as necessary. In most cases, any sensitivity or discomfort should subside within a few days of completing the whitening treatment.