Distichiasis (Double Eyelashes): Causes, Symptoms and Treatment

Distichiasis is an extra row of eyelashes that grows from the openings of the meibomian glands, the small oil glands along the edge of the eyelid, rather than from the normal lash line. It can be present from birth or develop later in life, and the extra lashes can rub against the surface of the eye.

Most people know it by its everyday name, double eyelashes. For some, the second row simply looks like unusually full lashes. For others, it brings red, watery, irritated eyes that keep coming back. This guide explains what distichiasis is, why it happens, what it can do to the eye and how eye doctors treat it.

Distichiasis at a glance

• What it is: a separate row of lashes growing behind the normal row
• Where the lashes grow: from the openings of the meibomian (oil) glands on the eyelid margin
• Types: congenital (present from birth) or acquired (after inflammation or injury)
• Main concern: extra lashes touching and irritating the cornea
• Who treats it: an eye doctor, usually an ophthalmologist

What is distichiasis?

The American Academy of Ophthalmology describes distichiasis as "a congenital or acquired condition in which an aberrant extra row of eyelashes emerges from the orifices of the meibomian glands." In other words, a hair grows where an oil gland opening should be.

The normal eyelashes grow from the front edge of the eyelid. The lashes of distichiasis sit a little further back, along the inner part of the lid margin, which is why they are more likely to brush against the eye every time a person blinks. The NCBI StatPearls chapter on diseases of the eyelashes defines it simply as "a separate row of lashes that is present behind the normal row of lashes."

What do double eyelashes look like?

The extra lashes run behind the usual lash line, closer to the eye. According to MedlinePlus Genetics, the extra eyelashes can range "from a few extra eyelashes to a full extra set." Cleveland Clinic notes that the extra lashes may be smaller than normal lashes and can point the wrong way, so a few fine hairs can be easy to miss, while a complete second row can make the lash line look fuller.

Because the difference can be subtle, a person may not realise the lashes are the cause of their eye irritation until an eye doctor examines the eyelid margin closely.

What causes distichiasis?

Congenital distichiasis

When distichiasis is present from birth, the cause is genetic. Cleveland Clinic explains that congenital distichiasis comes from "a genetic issue that happens during conception," and that in some of these cases the gene involved is the FOXC2 gene. StatPearls describes what happens during development: the pilosebaceous units "differentiate into lashes instead of meibomian glands."

Lymphedema-distichiasis syndrome

Congenital distichiasis can be part of an inherited condition called lymphedema-distichiasis syndrome. MedlinePlus Genetics describes it as a condition that affects the normal function of the lymphatic system, causing swelling of the limbs, typically the legs and feet, together with extra eyelashes. The extra lashes are present at birth, while the swelling most often begins during puberty.

The same source lists other features that can occur with the syndrome, including varicose veins, droopy eyelids (ptosis), heart abnormalities and a cleft palate. It is inherited in an autosomal dominant pattern, which means one copy of the altered FOXC2 gene is enough to cause the condition. Because extra eyelashes can be overlooked during a medical examination, MedlinePlus notes that some people with the syndrome may be diagnosed with lymphedema only.

Acquired distichiasis

Distichiasis can also develop later in life. StatPearls explains that this secondary form is seen in conditions that cause inflammation, which in turn leads to changes in the meibomian glands. Cleveland Clinic lists several possible causes:

• Blepharitis, a form of eyelid inflammation that may be chronic
• Meibomian gland dysfunction
• Ocular rosacea
• Chemical injury to the eye
• Stevens-Johnson syndrome
• Ocular cicatricial pemphigoid, an autoimmune disorder

Symptoms of distichiasis

Some people only notice the extra lashes. When the lashes touch the eye, symptoms listed by Cleveland Clinic can include:

• Visible extra eyelashes
• Redness, swelling or irritation of the eyes
• Watery eyes
• Sensitivity to light (photophobia)
• Eye pain
• A painful bump on the eyelid (stye)
• Frequent bouts of pink eye (conjunctivitis)

Can distichiasis damage your eyes?

It can. Lashes that repeatedly rub the front of the eye can cause scratches or scars on the cornea, according to Cleveland Clinic, and MedlinePlus Genetics also notes that the abnormal lashes can damage the cornea. That is one reason persistent irritation is worth having checked rather than ignored.

Cleveland Clinic's advice is clear: always contact a healthcare provider if you have eye irritation that you can't get rid of, or if you have eye pain.

How is distichiasis diagnosed?

Diagnosis is made during an eye examination. Cleveland Clinic explains that a healthcare provider can diagnose distichiasis with an eye exam that includes a slit-lamp test, which gives a magnified view of the eyelid margin, the lashes and the surface of the eye.

Because congenital distichiasis can be linked to lymphedema-distichiasis syndrome, which runs in families and can cause swelling in the legs, it can be worth mentioning any leg swelling or family history of similar findings at the appointment. People who already have a lymphedema diagnosis and notice extra lashes may want to raise it too.

Distichiasis treatment options

The choice of treatment usually depends on how many extra lashes there are and whether they are irritating the eye. Options fall into two groups: measures that protect the eye and procedures that remove or destroy the extra lash follicles.

Protecting the eye

Cleveland Clinic notes that non-surgical treatments may include eye drops and certain types of contact lenses, which can reduce friction between the lashes and the cornea. These measures ease symptoms but do not remove the extra lashes.

Plucking (epilation)

Removing the extra lashes gives quick relief, but the hair grows back. According to Cleveland Clinic, plucking only lasts two to three weeks, so it is usually a short-term measure rather than a lasting solution.

Electrolysis, radiofrequency and laser treatment

These treatments aim to destroy the root of each unwanted lash so that it stops growing. Electrolysis and laser thermal ablation are listed by Cleveland Clinic, and StatPearls also describes radiofrequency treatment of the follicles. Cleveland Clinic notes that several sessions are likely to be needed.

Cryotherapy

Cryotherapy uses extreme cold to destroy lash follicles. It appears among the treatment options described by both Cleveland Clinic and StatPearls, and as with electrolysis and laser treatment, more than one session may be required.

Eyelid splitting surgery

For a full extra row of lashes, an eye surgeon may recommend a lid-splitting procedure. Cleveland Clinic describes it this way: the provider divides the eyelid and removes the hair follicles. StatPearls also lists lid split among the surgical options.

The outlook for someone with distichiasis is generally good, according to Cleveland Clinic, although repeated treatments may be needed to clear the extra lashes. The right option is a decision for an eye specialist who has examined the eyelids.

Distichiasis vs trichiasis

The two conditions are easy to confuse because both involve lashes touching the eye. The difference is where the problem lies.

The American Academy of Ophthalmology explains that trichiasis is diagnosed when eyelashes emerge from their normal origin and curve inward toward the cornea, and Cleveland Clinic notes that trichiasis affects the normal set of eyelashes. StatPearls puts the distinction neatly: in trichiasis, "the lash follicle is normal, but the direction of lash growth is abnormal." Cleveland Clinic has a separate guide to trichiasis.

Did Elizabeth Taylor have double eyelashes?

She is widely reported to have had distichiasis. In 2011, NBC News reported that the actress's extra row of lashes was thought to be the result of a genetic mutation at the FOXC2 gene, and described distichiasis as a rare disorder.

Distichiasis, eyelashes and eyebrows: what hair restoration can and cannot do

Distichiasis is a medical eyelid condition, and it should be assessed and treated by an eye doctor. It is different from cosmetic concerns such as thin eyebrows or sparse lashes. Istanbul Care does not treat distichiasis or other eyelid conditions; its hair restoration work focuses on scalp, beard and eyebrow hair.

If your concern is thinning brows rather than extra lashes, these guides may help: why eyebrows stop growing back, minoxidil for eyebrows and what an eyebrow transplant involves. For scalp hair loss, start with the hair transplant guide.

When to see a doctor

See a healthcare provider if you notice extra lashes growing along the inner edge of the eyelid, or if you have eye irritation that doesn't go away, eye pain, repeated styes or repeated bouts of pink eye. An eye doctor can confirm whether distichiasis is the cause and discuss the treatment that suits your eyelids.

Sources

• Cleveland Clinic: Distichiasis (Double Eyelashes)
• American Academy of Ophthalmology: Eyelash disorders
• MedlinePlus Genetics: Lymphedema-distichiasis syndrome
• NCBI StatPearls, Patel BC, Joos ZP: Diseases of the Eyelashes
• Cleveland Clinic: Trichiasis (Misdirected Eyelashes)
• NBC News, 28 March 2011: Secret to Liz Taylor’s lush lashes: a genetic mutation