The synthetic phenyl-substituted analog of prostaglandin F2 alpha (PGF2-α), latanoprost, is an intraocular pressure-lowering drug for use in patients with primary open-angle glaucoma and ocular hypertension. Hypertrichosis of the eyelashes is a common reported adverse effect of this drug and of prostaglandin analogs in general since their introduction in the late 1990s.1 Here we present a case of poliosis and bilateral hypertrichosis of the malar vellus hairs that occurred during use of ophthalmic latanoprost solution for glaucoma treatment.
A 64-year-old woman presented at our department complaining of excessive hair growth in both malar areas. The problem had started 6 months earlier and the hairs had progressively grown in number and diameter since then. Examination revealed hypertrichosis and poliosis of the eyelashes in addition to hypertrichosis of the malar areas. The whitened eyelashes were interspersed among normal-appearing eyelashes in both eyes (Fig. 1). There were no signs of hypertrichosis on any other parts of the body. The patient had had bilateral glaucoma for 4 years, and had been using latanoprost eye drops since diagnosis. She had a history of hypertension and diabetes mellitus and had been taking amlodipine tablets and oral acarbose for the treatment of these diseases for about 8 years. She had no other cutaneous or systemic disorders and the results of routine biochemical and hormonal tests were within normal limits. She denied use of any topicals creams, including sunscreens or corticosteroids, on her face.
Hypertrichosis is the growth of hair that is considered excessive for the age, sex, and race of an individual. It can occur all over the body or be isolated to small patches. PGF2-α analogs have been observed to promote hair growth and may have hypertrichotic effects. The mechanisms by which prostaglandins trigger hair growth, however, are not clear. It has been suggested that hypertrichosis of the eyelashes following administration of prostaglandin analogs for glaucoma treatment is probably a result of the induction of the anagen phase in telogen-phase eyelash follicles.2 These analogs may also prolong the anagen phase of eyelashes, leading to an increase in eyelash length.3
Eyelash hypertrichosis has been reported as a common adverse effect of ophthalmic latanoprost treatment, with frequency rates as high as 77%4 and 50.5%.5 Even brief exposure to an ophthalmic prostaglandin analog appears to be associated with eyelash changes. In one study, very brief exposure to latanoprost (<22 days) was reported to produce hypertrichosis similar to that seen with sustained exposure.2 Our patient reported hypertrichosis of the vellus hairs of the malar area after 3.5 years of treatment.
Changes in the appearance of hairs other than eyelashes have been reported in a few papers. Reports of hypertrichosis of the vellus hairs of the eyelids,1,5 inner canthus,6 upper cheek,7 and malar regions8–10 can be found in the literature.
Chen et al.11 reported poliosis in a series of 7 patients using different PGF2-α analogs for primary open-angle glaucoma. The affected lashes were interspersed with normally pigmented lashes. Whole affected lashes were observed to be new, implying that the effect may result from failure of pigmentation in newly stimulated eyelash growth or from stimulated growth of previously inconspicuous white lashes. Our patient did not complain about her white eyelashes as she considered them to be normal age-related changes. It is, however, known that eyelashes do not generally turn white with age, and if they do, they normally only do so at a very late stage.3
Other local adverse effects of PGF2-α analogs are iris pigmentation, conjunctival hyperemia, increased pigmentation of the periocular skin, deepening of the eyelid sulcus, periorbital fat atrophy and relative enophthalmos, anterior uveitis, and an increased risk of herpes simplex viral infection recurrence. There have also been some reports of systemic adverse effects, such as symptoms of common cold and upper respiratory tract infection, headache, abnormal liver function tests, asthenia and hirsutism.12
We thought it might be interesting to report this infrequently observed case to highlight the importance of considering topical PGF2-α analog therapy as a possible cause of poliosis and hypertrichosis of the vellus hairs around eyes.
