An English man has suffered an extreme allergic reaction to Crest 1hr Express Strips, according to the Huffington Post.

Jake Barrett, 22, was said to have noticed a painful sac under his tongue 48 hours after using the tooth whitening kit, and was said to be unsure as to why it had formed. According to the report the sac was said to have expanded to a bulge over the proceeding few days which resulted in Barrett being barely able to swallow.

Barrett took himself to hospital where they determined the painful sac was filled with hydrogen peroxide – an ingredient that forms 15 per cent of the Crest whitening product – and had to undergo an emergency procedure to drain and remove the sac, leaving him with a hole under his chin.

According to the doctor, the sac was the size of a grape and could have leaked hydrogen peroxide down the patient’s throat. Barrett then had to have a ten day stay in hospital.

Procter & Gamble, parent company for Crest, is said to be looking into the incident, with a spokesperson issuing a statement that read, “Nothing is more important to us than the wellbeing and safety of the people who use our products.
“We’re sorry to hear about Mr. Bartlett’s experience and wish him a full recovery. Whilst not sold directly by P&G in the UK, Crest Whitestrips have been available in the United States for more than ten years, complying with all relevant legislation including peroxide levels. They are safe to use when applied as indicated on the packaging.”

Teeth whitening kits are thought to generally be safe when used correctly, albeit with some side affects such as tooth and gum sensitivity and discoloration from over-bleaching.