In addition to genetics, there are myriad triggers which can cause
hair loss. One many people may be familiar with is when shedding can occur after starting a new
medication - something which is generally listed on the accompanying patient information leaflet as a potential side effect.
Where this is not listed, people experiencing excessive hair fall they believe to be a result of their new treatment can report this - in the UK this can be done via the MHRA Yellow Card scheme - and this can help to identify further effects for exploration and, if it is found to be the case, these can be added to the potential side effects warnings.
Following a
2017 case report where a man being treated for type 2 diabetes with the prescription medications metformin and sitagliptin lost both his eyelashes and eyebrows, these drugs were linked to hairloss, raising more general concerns about this as a possible side effect. However, according to an article in Medical News Today, there have been only 'rare occasions' when people have reported a purported link between metformin and
thinning hair or hair loss.
Concerns about metformin causing hair loss
Whilst there is no proven direct association between metformin leading to hair loss, there is research that suggests an indirect link. A clinical study published in the Journal of Clinical Endocrinology and Metabolism in 2016 entitled 'Long-term Metformin Use and Vitamin B12 Deficiency in the Diabetes Prevention Program Outcomes Study', found that "Long-term use of metformin in DPPOS was associated with biochemical B12 deficiency and anemia. Routine testing of vitamin B12 levels in metformin-treated patients should be considered".
Vitamin B12 deficiency - also known as
pernicious anaemia - has a number of symptoms, one of which is hair loss. This type of
dietary-related shedding occurs diffusely from all over the scalp and is known as
Chronic Telogen Effluvium. Although it can last six months or more, it is considered a temporary hair loss condition.
Thinning hair may be due to health issues
Metformin is used to treat diabetes and
polycystic ovary syndrome (PCOS). Both these health issues come with their own hair loss associations so it may be more likely that the underlying illness is the cause of shedding, rather than the medication.
The hormonal imbalance created by increased androgen levels in women with PCOS can cause diffuse thinning. This can also present in people with
type 2 diabetes who have insulin resistance. Furthermore, high blood sugar can damage blood vessels, preventing the follicles from receiving the necessary supply of nutrients and oxygen needed for healthy hair growth, also resulting in thinning hair.
Whilst addressing these health issues should be the key priority, once these are being properly managed, hair loss can also be dealt with. Anyone worried about unusual levels of hair fall or intensely thinning hair is best advised to speak to a hair specialist who, following a consultation, can diagnose their condition and, where appropriate, recommend suitable
hair loss treatments for consideration.