What Causes Exclamation Mark Hairs?'

Name: Rachel

Question: some of my shedded hairs are noticeably thinner toward the root, they get thinner around 6-10 cm from root. is that considered an exclamation mark hair? or do exclamation mark hairs get thinner in closer proximity to the root? also, could you please detail what sort of allergies can cause this? thank you

Answer: Hi, Rachel. Exclamation mark hairs tend to thin in closer proximity to the scalp than what you describe here.

They occur naturally and are a key feature in diagnoses of the autoimmune hair loss disorder Alopecia Areata, often found surrounding the rounded bald patches symptomatic of this condition, especially in its early days.

Though allergies are one of a number of factors known to trigger Alopecia Areata - hence their association with exclamation point hairs - the specific allergies and causes are as yet unconfirmed. It is suspected that allergies to dust mites may cause the condition and, given Alopecia Areata is an autoimmune disease and people affected by one immune-related disorder are more likely to experience others, issues such as coeliac disease (autoimmune gluten intolerance), and atopic conditions including hayfever and asthma may also be present in people with Alopecia, but whether they are the actual cause remains unknown.

Interestingly, anti-histamines - traditionally used to treat hayfever - have also been trialled as a potential treatment for Alopecia Areata, though these studies were perhaps not as successful as previously hoped given the lack of follow-up. When it comes to the scalp-only phenotype, Alopecia Areata treatment is possible but involves topical solutions.

This is an extremely active area of research so it is hoped that more will be known about the mechanisms of precisely what causes Alopecia Areata, and the environmental and genetic factors which may further provoke autoimmune alopecia, in the future. For now though, it remains a fairly enigmatic condition which can affect men, women and children of all ages and races.

However, it is worth noting that this 'exclamation mark' hair shape has also been found in cases of trichotillomania - as documented in a 1993 investigation into the diagnostic relevance of exclamation mark hairs - so, whilst it is most commonly associated with Alopecia Areata, that is not the only form of hairloss it pertains to.

If you are concerned about excessive hair fall we recommend having a professional consultation as this will get to the bottom of the cause of any hair loss. The specialist you see can also answer your questions and provide you with personalised recommendations for treatment, where appropriate.