Eyelashes are specialized hairs that protect the eyes from dust, debris, and sweat. Unlike the hair on the scalp, which has a very long growth phase, an eyelash’s life cycle is significantly shorter and more synchronized. If a lash is lost, it will generally grow back, provided the hair follicle remains undamaged. The speed and success of this regrowth depend entirely on where the lost lash was in its natural cycle and the cause of its removal.
The Eyelash Growth Cycle
Eyelashes follow a precise, three-phase growth cycle, though the duration of each phase is highly condensed compared to other body hair. The entire cycle for a single lash takes anywhere from four to eleven months to complete.
Anagen Phase
The Anagen phase is the active growth stage, typically lasting only 4 to 10 weeks. During this time, the lash is firmly attached to the dermal papilla, which provides blood supply and nutrients. The brevity of this phase is why eyelashes do not grow as long as scalp hair.
Catagen Phase
The Catagen phase is a short transitional period lasting approximately two to three weeks. The eyelash stops growing, and the hair follicle shrinks and detaches from the blood supply. If a lash is lost during this phase, regrowth will not begin until the follicle completes the cycle and resets.
Telogen Phase
The final phase is Telogen, the resting and shedding stage, which lasts for three to four months. The old lash sits dormant while a new hair forms beneath it in the same follicle, eventually pushing the old lash out. Since each lash operates on its own timeline, only a small percentage are shed at once, preventing noticeable gaps.
Regrowth Timeline After Plucking
When an eyelash is forcibly pulled out, especially by the root, it prematurely disrupts the natural cycle, forcing the follicle to reset its timeline. A lash that falls out naturally was already in the Telogen phase, meaning a replacement was likely preparing to emerge, resulting in a quicker replacement.
Pulling a lash out during the active Anagen or transitional Catagen phases removes the hair shaft before its natural shedding time. This forceful removal means the follicle must restart the growth process from the very beginning of the Anagen phase. The follicle requires a period of recovery and rest before it can successfully initiate new growth.
For a pulled eyelash, the typical regrowth timeline is significantly longer than a natural shed, generally ranging from six weeks to three months for the lash to return to full length. If the follicle was not structurally damaged, the new lash will grow at the standard rate of about 0.12 to 0.14 millimeters per day. Patience is required, as the full length will not be visible immediately, but the process has begun as long as the follicle is intact.
Causes of Delayed or Impaired Regrowth
While most eyelashes grow back, certain factors can significantly delay or prevent their successful return. The most common cause of impaired regrowth is damage to the hair follicle itself. Trauma, such as a severe burn or chronic mechanical stress, can cause scarring within the eyelid margin, preventing the follicle from producing a hair shaft.
Repeated, forceful pulling, such as with the condition trichotillomania, can lead to permanent damage and scarring of the follicle. This condition, known as traction alopecia, compromises the follicle’s ability to initiate a new Anagen phase, potentially resulting in permanent lash loss.
Underlying medical conditions can also interfere with the growth cycle. Known causes of lash loss include thyroid disorders and autoimmune conditions like alopecia areata, where the immune system mistakenly attacks hair follicles. Chronic inflammation of the eyelids, known as blepharitis, can also block or damage the follicles over time. Addressing these systemic health issues is necessary for consistent and successful lash regrowth.