If you scan through the diagnostic and statistical manual (DSM) you will find a large number of rather unusual diagnoses. In the medical field it is the same. They have their own diagnostic manual and one of the more rare disorders is known as Hypertrichosis. Some refer to this disorder as "Human Werewolf Syndrome." The medical condition known as Hypertrichosis leads to an abnormal growth of hair in locations of the body that it does not usually grow. In some cases it only develops in specific areas while others end up with hair all over their body. While some individuals develop this medical condition during latter parts of their life, most are born with this condition.
So, why do certain individuals have "Human Werewolf Syndrome?" The belief is that this medical condition occurs during pregnancy. In a normal pregnancy very thin hair like structure covers the body, this is called lanugo. Usually the lanugo falls off the body in about the eighth month. For those that have been diagnosed with Hypertrichosis, the hair never falls off. Actually, it continues to grow.
In cases where Human Werewolf Syndrome occurs later in life (Acquired Hypertrichosis), hair begins to cover localized areas of the body or in some rare cases it can go on to cover the entire body. This is a very rare condition.
So, what really does cause Human Werewolf Syndrome? Actually, there are no definite answers to this question most researchers hold to the idea that there is a genetic component to it. Whether it occurs as a result of the mutation of genes or it happens because of a genetic predisposition is not certain.
What can be done to treat Hypertrichosis? Obviously, an individual can shave on a regular basis.