Short answer: teeth whitening shouldn't hurt. Some people feel a little tingling or sensitivity during or after a session, and that's normal and temporary. The good news is that most of it can be avoided with a few simple habits.
Why whitening can cause sensitivity
Whitening gel uses peroxide to break down the stain molecules sitting in your enamel. To do that, it has to travel through the enamel's tiny pores. Some of it reaches the dentin underneath, the layer that connects to the nerve of the tooth.
That's why some people feel a brief zing, especially with cold drinks or cold air. It's a temporary reaction, not damage, and it usually settles within a day or two.
Who is more likely to feel it
- People who already have sensitive teeth
- Anyone with receding gums or exposed roots
- People with worn enamel, small cracks or untreated cavities
- Anyone who leaves the gel on longer than the instructions say
If you have cavities, gum problems or recent dental work, check with your dentist before you whiten. Whitening won't fix those problems, and they can make sensitivity worse.
7 ways to whiten without the zing
- Start using a desensitising toothpaste a week or two before you whiten. Keep using it throughout your treatment. We recommend this with every kit.
- Build up your session time. Our kit allows up to 40 minutes per session in 10-minute blocks. If you're sensitive, start with one or two blocks and build up as your teeth feel fine.
- Keep gel off your gums. You only need about 0.5ml per side of the tray, enough to coat the front of your teeth. Wipe away any gel that touches your gums.
- Space out your sessions. Stick to the recommended schedule: three sessions in the first week, then one every 3–6 weeks. More often doesn't mean whiter, just more sensitive.
- Skip very hot and very cold food and drinks for 24 hours after a session. Your teeth are most reactive straight after whitening.
- Brush gently with lukewarm water. Hard brushing straight after a session can make sensitivity worse.
- Use a pen for top-ups. Once you've reached your shade, a Teeth Whitening Pen gives a quick 60-second touch-up. That's far less contact time than a full tray session.
How long does sensitivity last?
For most people, any tingling fades within 24–48 hours of a session. If it's still there after a few days, or it's sharp rather than mild, stop whitening and see your dentist. That can be a sign of an underlying problem that's worth getting checked.
The bottom line
Whitening with a properly formulated gel, used as directed, is comfortable for most people. A little patience goes a long way: build up slowly, protect your gums and give your teeth time to recover between sessions.
New to whitening? Our Teeth Whitening Kit comes with step-by-step instructions to help you whiten safely and comfortably at home.