Eyelash mites (Demodex mites) are microscopic organisms that naturally live on most people’s skin, especially around hair follicles and oil glands. In normal amounts, they’re harmless, but when they multiply excessively, they can lead to eye and eyelid problems.

There are two main types: Demodex folliculorum, which lives in hair follicles like eyelashes, and Demodex brevis, which prefers oil glands. Overgrowth can happen due to factors like aging, weakened immunity, or poor hygiene.

When this imbalance occurs, it can cause a condition called blepharitis (eyelid inflammation). Common symptoms include red, swollen, or itchy eyelids, a gritty or burning feeling in the eyes, crust or debris at the base of eyelashes, thinning lashes, increased sensitivity to light, and sometimes lash loss.

Not everyone with these mites experiences symptoms, so many people don’t even know they have them unless irritation develops or is checked by an eye doctor.

Treatment and prevention mainly focus on hygiene. Regularly cleaning the face—especially the eyelid area—with a gentle, fragrance-free cleanser can help keep mite populations under control. In some cases, doctors may recommend specific eyelid cleansers or treatments if symptoms are more severe.

If you notice persistent irritation or any of the symptoms above, it’s best to consult a healthcare professional or eye specialist for proper diagnosis and care.