Traditional Anticoagulants and Hair Loss: A Role for Direct Oral Anticoagulants? A Review of the Literature

Abstract

Hair loss is associated with the anticoagulants heparin and warfarin. With the recent availability of direct oral anticoagulants (DOACs) it is of clinical interest to know if they are implicated with hair loss and/or whether they could be successfully prescribed for patients who suffer from coumarin- or heparin-related alopecia. Initially reports of heparin- and coumarin-associated alopecia available through PubMed and Medline were explored in order to establish the cause of this side effect. Currently there is a lack of unanimity on why anticoagulants cause alopecia. However, timing and presentation strongly suggest that telogen effluvium is part of the process. The observation that both heparins and coumarins cause a similar pattern of hair loss suggests a shared mechanism related to anticoagulant activity. To date, the World Health Organization has received 405 reports of DOAC-associated alopecia through their pharmacovigilance database VigiBase®. Additionally, real world registry data describes an alopecia incidence of 4.4 per 100 patient years in patients prescribed rivaroxaban and dabigatran. Further widespread clinical experience is required to ascertain if this is true, but early indications suggest that DOACs are implicated in hair loss and will not provide a suitable alternative for patients suffering from alopecia related to traditional anticoagulants.

Warfarin-Induced Alopecia: A Rare Case Report

“…Only a few cases have been reported worldwide on warfarin-induced alopecia. As per literature search, it was found, 14 case reports of warfarin-induced alopecia published so far [5]. Hair fall due to the drug is an idiosyncratic adverse reaction of unknown mechanism.…”

“…The first case of warfarin-induced alopecia was reported in a 2-year-old girl following ingestion of rat poison, which has warfarin as the active ingredient. Hair fall is also associated with other oral anticoagulants and as per WHO-Uppsala Monitoring Centre VigiBase877 cases of warfarin alopecia had been recorded [5].…”

“…TE is strongly suspected as the mechanism due to timing and presentation of hair loss induced by warfarin. Another mechanism attributed to warfarin-induced hair loss includes change in vasculature of scalp leading to focal degeneration of the connective near the blood vessels of follicular connective tissue sheath [3,5]. It is also noted that when the hair follicles enter the telogen phase asynchronously following chronic exposure of drugs, the hair fall becomes clinically significant only after months or years of treatment with the offending drug.…”

“…As per previous literature evidence, the alopecia caused by warfarin is usually reversible and it reappears on rechallenge. The time range of warfarininduced alopecia is from 3 months to 13 years [5]. There are more reports with women having alopecia following warfarin compared to men.…”

“…There are more reports with women having alopecia following warfarin compared to men. This gender variation is attributed to frequent grooming of hair by females which might aggravate the shedding of the resting hair resulting from TE [5].…”