Agent specific effects of anticoagulant induced alopecia

Abstract

Summary Alopecia has been observed with many anticoagulants although the mechanism is unclear. A 20 year old female with recurrent DVTs developed alopecia with multiple anticoagulants, including heparin derivatives and the new oral anticoagulants. This resolved with discontinuation of the agents. The patient was ultimately able to be anticoagulated with fondaparinux long term without any alopecia. This case addresses the key clinical question of management and recognition of anticoagulant induced alopecia. This side effect can result from almost any of the available agents and is quickly reversible, underlining the importance of tailoring treatment to the individual and their experiences.

Alopecia em pacientes anticoagulados

“…Interruption of the growth phase causes abnormal loss of anagen hairs (anagen effluvium). [1][2][3][4][5][6][7]…”

“…[8][9][10] Anticoagulants act on the anagen phase of hair growth, stimulating the follicle to prematurely enter the telogen phase, generally leading to visible alopecia around 2 to 4 months after administration is initiated. 2,5,7,8 One hypothesis is that anticoagulant-induced alopecia might be caused by disseminated thrombosis in the microcirculation of capillaries that feed the roots of the hair, but this has not been proven scientifically. 4 Another hypothesis, based on scalp biopsies, is that there may be distension of bundles of the dermis caused by bleeding with focal degeneration of collagen bundles, which would provoke strangulation of the hair root and injury to the connective tissue of the dermal papilla.…”

“…3 Heparins and AVKs are the anticoagulants associated with this condition, with reported incidence rates from 30 to 40% with AVKs and 54 to 66% with UFH. 7 Hair loss secondary to use of anticoagulants normally has onset in the frontotemporal area, later extending to the remainder of the scalp. However, it may continue even when anticoagulation is withdrawn, taking up to 3 months for spontaneous regrowth of hair to begin.…”

“…However, it may continue even when anticoagulation is withdrawn, taking up to 3 months for spontaneous regrowth of hair to begin. 4,7…”

“…5,6,8,9 The occurrence of alopecia clinically associated with warfarin is common and is more frequent among female patients, with overall reported incidence from 30 to 40%. 1,2,7,9,10 Characteristics such as older patient age, longer duration of treatment or higher dosage are risk factors associated with the condition and the majority of reports reveal that alopecia is reversed when treatment is withdrawn. 5,[11][12][13][14]…”