Whitening shouldn't hurt. The most common side effect is temporary tooth sensitivity, a brief zing with hot or cold drinks that usually fades within a few days.
Starting with a dental checkup helps. Cavities, worn enamel, or receding gums can make sensitivity worse, so it's best to handle those first.
If your teeth get sensitive, a toothpaste for sensitive teeth can help, and your dentist can adjust how you whiten. Also remember that fillings and crowns don't whiten, so ask about any in visible spots before you start.
Learn about whitening at Luminous Smiles.
This article is general information, not medical advice. Call us with questions about your own teeth.