About one in four to five people who get COVID-19 eventually start noticing hair loss. Unlike shortness of breath, loss of energy, or headaches, it doesn’t interfere with daily activities, but it’s still bothersome, especially when hair falls out in clumps and the thinning of your hair is conspicuous. If this is your case, don’t worry: it’s probably just a matter of waiting
How does hair fall out after COVID-19?
Usually the problem doesn’t occur immediately. According to a survey of 128 patients from different countries, about half of them started losing their hair in the first month after being infected with the coronavirus, and the rest started losing their hair 12 weeks later (by the way, this variation is unusual, more on that below).
Often the hair loss is more or less even, and not in one area of the head. Some people start to suspect something is wrong when they tuck them into a ponytail and notice that the rubber band has to be tightened tighter, while others pay attention to the fact that there is more hair than usual in the bathroom drain, on the comb or on the pillow. In the scientific literature, we haven’t come across cases so severe that a wig is needed, but it does happen occasionally with telogenic hair loss.
What is telogenic hair loss (THL)?
THL is the most common reason for hair thinning after COVID-19 – there is a disruption in the hair growth cycle.
It seems like the hair on your head is growing all the time, but it really isn’t. Most of the time, the hair follicle is actually in the growth phase (anagen) – the hair lengthens, but after a short transitional period (catagen), the resting phase (telogen) occurs. The hair then falls out, and a new hair usually appears in its place. As a rule, the whole cycle takes several years.
Normally, 85-90% of about 100,000 hairs grow. The bulbs of the remaining ones are either in catagen or telogen. Every day a person loses about a hundred hairs, i.e. only about 0.1%. But sometimes a lot more bulbs go into the telogen phase. It usually lasts about three months. When the telogen ends, a lot of hair falls out. That’s what THL is.
What causes hair falling?
THL can be associated with a variety of things: sudden weight loss, poor diet, childbirth, withdrawal of oral contraceptives and other changes in hormone levels, surgery, an illness, especially one with fever (such as COVID-19). THL can even be triggered by severe stress. This may be why, during the pandemic, even those who avoided being infected with the coronavirus began to complain to doctors. And in a third of cases, the cause of DVT cannot be determined.
The mechanisms of THL are not fully understood. In the case of COVID-19, there must be several, as some people experience hair loss after weeks and others after three months or later.
Doctors and scientists who conducted the aforementioned patient survey suggested that early hair loss may be due to poor blood circulation in the hair follicles due to micro clots (clots are a common problem with coronavirus infection). It is possible that the hair growth cycle is disrupted by the coronavirus itself or by molecules that are produced by the body for an immune response. It is also possible that COVID-19 medications can cause hair loss.
How can hair loss be stopped?
Essentially, with THL, the hair follicle is ahead of the events within a single cycle. In the vast majority of people, the cycle recovers on its own – you just have to wait. Usually, hair falls out for three to six months, and then new hairs take its place. After about another three months, your hair is as thick as it was before the disease. Recovery may be faster after COVID-19: In one study, most of the 30 participants stopped losing hair in less than two months, and some in just 12 days.
If your hair has been falling out for longer than six months, the cause is most likely unresolved. It’s often stressful, so if, after experiencing COVID-19, you see hair on your pillow or comb, try not to think about it or worry about it.
A therapist, dermatologist or trichologist (hair specialist) will help to rule out other possible causes of hair loss: medications, hormonal imbalance, lack of any substances. Sometimes doctors prescribe drugs to stimulate hair growth, but most likely this will not be necessary. Vitamins should also not be taken without a prescription (hair can fall out and from their overabundance).
What if it’s not telogenic loss?
In fact, one of the hypotheses above suggests that sometimes after COVID-19, not telogenic but anagenic hair loss develops. One such case has even been described in the scientific literature, but may have been misdiagnosed. However, anagen loss also stops on its own.
Those who have been lying motionless in the ICU for a long time may have impaired circulation of the scalp – the area of contact with the pillow will form a spillage.
Finally, pandemic stress can accelerate hair loss in those who had baldness even earlier. But, again, if your hair was fine and started falling out after COVID-19, you almost certainly don’t have to worry about it.