En español | How's this for unsettling? Right now, as you are reading these words, microscopic parasites (known as Demodex mites) are living in your eyelashes.
What the heck are they doing there? Well, these critters crave oil, which makes the edges of your eyelids prime real estate, since each edge is lined with 25 or so sebum-producing glands. These mites aren't crazy about light, so during the day they burrow deep in the eyelash follicles and snooze.
They come out at night, while we're sleeping, and have a party — mating and munching on dead skin cells. “That's why we tend to have more crusting around our eyes when we wake up,” says Julie Lam, an optometrist in Cave Creek, Arizona. When fun time is over, they crawl back into our hair follicles to lay their eggs.
Before you make a beeline for your bathroom mirror, magnifying glass in hand, there are a few things you should know. First of all, you can't see these mites. Also, and this is somewhat reassuring, we all have small numbers of them; they're part of our bodies’ normal microbiome.
"In small numbers, Demodex mites typically aren't a problem,” reassures Scheffer Tseng, M.D., a Miami-based ophthalmologist. “However, if they reproduce in large numbers, you reach a threshold.” That's when things can turn kind of, well, icky.
Eye and skin problems associated with mites
Blepharitis. “Blepharitis is the number one common disease associated with mites,” Tseng says. This inflammation of the eyelids, which typically occurs as a result of a blockage in the oil glands at the base of the lashes, can be caused by an infestation. What's more, Demodex mites carry bacteria and release it into the skin, triggering irritation and inflammation on the lids that can lead to the signature symptoms: crusty lashes, itchiness in the surrounding skin, fluctuating blurry vision, and red, swollen, watery eyes. (Making matters worse, the mites feed on the ensuing crusting, exacerbating the condition.) And the eggs that they lay at along the base of the lashes can lead to trichiasis (misdirected lashes) or lash loss.
Rosacea. Demodex mites also frequently occur in greater numbers in those with rosacea, leading to flare-ups. In fact, people with the skin condition have about 18 times more mites. “We're still trying to figure out the connection — whether Demodex mites are the cause or result of rosacea,” Lam says. However, according to the National Rosacea Society, “Evidence appears to be mounting that an overabundance of Demodex may possibly trigger an immune response in people with rosacea, or that the inflammation may be caused by certain bacteria associated with the mites."
How to handle a possible mite overload
See your doctor if you experience possible symptoms of an outbreak. They can carefully remove individual lashes and look at them under a microscope to see if there are mites stuck to the hair follicles.
The most effective way to eliminate a mild infestation is daily eye hygiene. Clean the eye area twice a day, with warm water and a gentle cleanser. Less-than-clean skin supplies mites with extra lipid nourishment, encouraging them to stick around and reproduce. “You don't necessarily have to kill the mites, you just need to prevent the mites from mating,” Tseng says. “They will eventually die off.”
Even better, pick up a package of eyelid wipes. The back-and-forth cleansing motion tends to be more efficient in clearing away makeup, oil and other buildup on eyelids, says Lam, who prescribes Ocusoft lid scrubs to patients. Wrap one around your finger and lightly scrub along the base of the top and bottom lashes, then rinse off.
If you have a bout of blepharitis, apply a warm, moist washcloth over clean eyes for a few minutes every day. The warm moisture will make it easier to wipe away crusty buildup and keep lids and lashes clean. It will also help reduce gland secretions, which bring on the bacteria that cause irritation. And the fewer secretions, the fewer mites you'll have since they'll have less to feed on.
More serious outbreaks
"Blepharitis is usually bacteria-based, so when you clean around the eyes, it usually gets better,” says Lam. But if cleaning around the eyes doesn't reduce symptoms, Lam says, “you have to be a bit more aggressive.”
Tea tree oil, swiped along the lash line, is a kind of kryptonite to mites. “In its pure form or in high concentrations, tea tree oil contains chemical components which can be extremely irritating,” says Tseng, who suggests using a kinder, over-the-counter formulation infused with diluted tea tree oil. One such product, Cliradex, contains a potent component in tea tree oil — terpinen-4-ol. It works by killing mites directly and disrupting the life cycle to prevent reinfestation, as well as easing symptoms such as itchiness.
"The total life cycle of mites is several weeks,” says Lam. “But I usually have patients on tea tree wipes for at least 30 to 60 days, depending on the severity of the condition.”
In-office procedures, such as eyelid microexfoliation, may also be recommended to offer relief to those with blepharitis-related issues. BlephEx, for example, employs a device with a rotating sponge tip to dislodge debris, crusting and remains of bacteria along the lash line. For a severe infestation, your eye doctor may prescribe a medicated ointment, which is rubbed along the lash line. Not only will it fight bacteria and ease inflammation, it will help prevent mites from moving around — and multiplying. Additional antibiotics and/or steroids may be needed to treat underlying skin conditions.