Some hormonal disorders in women can lead to the growth of thick or dark facial hair, called hirsutism. Hirsutism can also be a side-effect of taking some medicines. It occurs either as a result of an increased production of an androgenic hormone (such as the male sex hormone testosterone), or because the skin has become more sensitive to this type of hormone.
This is a companion discussion topic for the original article at https://patient.info/medicine/eflornithine-cream-vaniqa