Some optometrists say they're seeing an increase in cases of lash lice, known by its medical term, Demodex.
Some people have tried to stay away from cleaning them at all. But that leads to an increase in bacteria, which harbors more bacteria and leads to infections.
Symptoms include itchiness, redness and inflammation, and what may be even more alarming, the lice.
The lice are organisms that live on the hair follicle. It's just like having head lice, which could be transferred to anyone.
Dr. Sairah Malik says lack of cleaning leads to the bacteria buildup.
"Generally the idea when you have eyelash extensions is that people are afraid to kind of touch them or wash them because they're afraid the eyelash will fall out," Dr. Malik said.
She adds cleaning your eyelids is critical.
"We recommend tea tree base cleanser. Any cleanser that has a diluted form of tea tree, and it is a good idea to use on a daily basis," Dr. Malik explained.
Tea tree oil is an essential treatment for hair, skin and nails and can be antibacterial.
To be safe, she says it's a good idea to give your eyelids a break from lash extensions every now and then.
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