Hansen's disease, also known as leprosy, is an infection of the skin and nerves caused by the bacterium Mycobacterium leprae. The disease often affects the skin of the eyebrow region, leading to loss of sensation and permanent loss of the eyebrow hairs. There are numerous other rare and uncommon causes of eyebrow hair loss, including vitamin A toxicity, nutritional disorders and other dermatological disorders. If you experience loss of eyebrow hair, see your doctor to evaluate the cause and to discuss a treatment plan.
Also called “chastetree,” Vitex is an herb which is typically prescribed to treat estrogen dominance. It seems to be recommended as a remedy for especially low levels of estrogen as well however, and does seem to have a general balancing effect on the overall ratio of estrogen to progesterone. Vitex’s balancing effect is thought to result from the stimulation of dopamine production.
It’s natural for estrogen levels to fluctuate throughout a woman’s life, but drastic drops can disrupt the hair growth cycle and cause telogen effluvium. For example, during pregnancy, a woman’s estrogen levels are at their peak. Fewer hair follicles enter the telogen stage of the hair cycle, so hair looks thicker than usual. A few months after pregnancy, however, estrogen levels drop and the excess hair falls out. While totally normal, this type of telogen effluvium can be very upsetting for new mothers.
Eyelash hairs are usually present in two to three rows, and are short, thick, and curved in appearance. They are set obliquely, anterior to the palpebral muscle. The upper eyelashes are more numerous and curve upward, while the lower eyelashes curve down in order to avoid interlacing during eyelid closure. Eyelash cilia are unique in that they have no erector muscles. Eyelash hairs are oval in all races.
Thyroid hormone receptors were detected in both dermal and epithelial compartments of the human pilosebaceous unit. T4 and T3 decrease the apoptosis of hair follicles and T4 prolongs the duration of anagen in vitro. Thyroidectomy delays initiation of anagen. Administration of thyroxine advances anagen, initiation of which is however delayed once toxic doses are given. Therefore, ratio of telogen to anagen hairs is increased in hypothyroidism as well as hyperthyroidism. Thus, the hair follicles are affected in thyroid disorders, and madarosis is caused due to disturbances in hair cell kinetics. Hypothyroidism is associated with generalized hair loss probably due to coarse, dull, and brittle hair with reduced diameter. The eyebrows and eyelashes may also be lost. Loss of lateral one-third of eyebrows known as Hertoghe sign is a characteristic sign of hypothyroidism. Some people also refer to it as Queen Anne's sign, after Anne of Denmark whose portrait with shortened eyebrows has been interpreted by some as indicative of the presence of goiter, even though such a fact has not been proved by any known sources of information. Madarosis may even be the presenting sign in hyperthyroidism. In hyperthyroidism, there is thinning with breaking off and shortening of hair. Madarosis can also occur in hypopituitarism, hypoparathyroidism, and hyperparathyroidism.