Why Don't Eyelashes Grow?

Eyelashes, technically called cilia, are short hairs that fringe the eyelids. While they help to clear debris from the eye, they are primarily valued for their appearance.

Growth

• Hair grows and rests in a cycle. The active phase is very short for eyelashes, about 30 to 45 days, compared to two to six years for scalp hair. This is why eyelashes stay short.

Resting

• The phase during which the hair follicle is dormant lasts about 100 days for scalp hair, but is much longer for eyelashes, eyebrows and other body hair. Since lost hairs aren't immediately replaced, it may seem as if they aren't growing at all.

Random

• While some mammals shed hair on a seasonal basis, human hair growth is random. Some hair will be in each of the phases of growth at any particular time.

Drug treatment

• The FDA has approved a drug called Latisse for treating hypotrichosis, a condition in which the patient has no eyelashes. It may also treat eyelash loss due to chemotherapy.

Cautions

• Latisse manufacturer Allergan warns that it can change the color or pigmentation of the eyelid or the iris itself, making the eye color more brownish.