A man’s eyelashes grew unusually long and developed a dramatic curl, a side effect of his cancer treatment with an epidermal growth factor receptor (EGFR) inhibitor. Doctors referred to the patient’s sudden eyelash growth as “drug-induced trichomegaly,” a condition characterized by excessively long eyelashes, typically exceeding 12 millimeters. Trichomegaly involves eyelashes becoming curlier, thicker, and darker. Several medications, including EGFR inhibitors like panitumumab, can trigger trichomegaly. EGFR inhibitors work by blocking EGFR in the body to increase tumor cell self-destruction and suppress growth. However, EGFR is not exclusive to cancer cells; it is also found in healthy tissues, including skin and hair follicles. Evidence suggests that blocking EGFR prolongs the stage where hair actively grows and is associated with increased hair coarseness, curliness, and new hair follicle formation. The resulting eyelash growth is a well-established potential side effect of EGFR blockers. Besides chemotherapy drugs like panitumumab, other medications, such as hormone-like drugs used to treat infertility, can also trigger trichomegaly by boosting eyelash growth. Trichomegaly can also occur due to infections or genetic syndromes that affect the response to growth factors. In the reported case, the man’s eyelash growth appeared within the first few months of treatment and subsided after the treatment ended. He was advised on safe eyelash trimming to manage his extra-long lashes. Trichomegaly is generally harmless unless the eyelashes grow towards the eyeball, known as trichiasis, which can damage the eye’s outer layer and potentially lead to vision loss or even blindness in severe cases.
Unusually Long and Curly Eyelashes: A Side Effect of Cancer Treatment
