Isabelle Klun got eyelash extensions. Her eyes swelled up so much she couldn't see.

Eyelash extensions are great. For those not blessed with long lashes naturally, they’ll give you thick, dark lashes without having to faff around with falsies every day. They also save loads of time getting ready in the morning.

But when not done properly or by someone lacking the proper training, things can go wrong.

Isabelle Klun had been getting eyelash extensions every two to three weeks for about a year. Then one application left her unable to see and struggling to breathe.

The 20-year-old from Ottowa, Canada told CTV News she had them done on a Tuesday and by Thursday she’d experienced a very bad allergic reaction.

"My girlfriend had slept over and I couldn’t even see her. And, I was having a hard time swallowing and even breathing," she told the news outlet.

She said she went to hospital where they admitted her "within seconds" when they saw her face, with the areas above and under her eyes severely swollen. Her tonsils were also "really inflamed".

The nursing student said she had noticed some swelling after her previous treatment, so this time asked the esthetician for the name of the eyelash adhesive they were using to see if it was the same one, which she believed she was allergic to.

She told her she wasn't sure but that she "should be good".

"So I said okay. I continued with it when I really shouldn’t have. I shouldn’t have done it when I heard she didn’t even know what glue she was using or what the ingredients were or anything,” Kun said.

At the hospital, she was given an antihistamine and steroid intravenously to try to reduce the swelling before being sent home with antihistamine tablets.

Because the swelling prevented the removal of the adhesive, Kun said as of Thursday her eyes had not improved. "There’s like a sac of fluid under my eye now. It’s so gross."

The owner of the beauty salon declined to comment on Kun's case in particular but told CTV News that she would offer allergy testing to clients who requested it.

Unaware that developing a sudden allergy was even possible, Kun's advice to other women getting the service was to always request an allergy test.

"Also be very careful where you go. These people are dealing with your eyes, with your vision. I mean, this morning I woke up and I wondered if I would ever be able to see again,” she said.

She said she would be getting extensions again in the future.

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