The condition known as anagen effluvium (AE) is the name of a condition that causes hair to no longer actively grow despite being in the growing state (anagen).
An environmental factor either causes hair cells to stop dividing, or prevents the key enzymes from converting into important steroids necessary for the keratinization process to take effect. This environmental shock causes the hair to become quite brittle and break away with minimal effort. Instead of shedding at the root as a normal healthy hair would, hairs impacted by anagen effluvium will break off at the hair shaft itself.
AE may cause hair to fall out for two main reasons:
Pemphigus vulgaris is an autoimmune disease that causes the body to produce autoantibodies that attack protein cells on the epidermis (skin). This results in blisters and sores that can sometimes result in hair loss, although this particular side effect is quite rare.
Hairs that are affected by telogen effluvium (TE) are much different than hairs affected by AE. As mentioned before, AE causes the hair shaft itself to fracture as opposed to TE, which makes the hair shed like normal. With anagen effluvium, there is no “club hair” (fully mature keratinized hair) that signifies TE because the hair itself is still undeveloped.
The main difference, however, is the rapid onset of anagen effluvium . AE causes a rapid rate of hair loss, typically within a number of days or weeks after an environmental impact shocks the follicles. With TE, however, hair loss will not become apparent until months later. Sometimes, Anagen effluvium and TE can work in tandem. This results in total baldness.
Typically, your doctor will be able to diagnose anagen effluvium after reviewing your medical history. Chemotherapeutic agents are almost always the cause. However, your doctor may wish to examine your scalp so as to rule out any additional possibilities.
Usually removing the environmental irritator is enough to allow hair to begin growing once again, provided that the hair follicle is not completely destroyed. The majority of people recovering from chemotherapy are able to grow hair after the cessation of treatment. The mitotic activity is able to resume, and the hair shaft regains normal density so as not to fracture.
Certain medications can also help anagen effluvium as well. Minoxidil is a topical treatment that is thought to shorten the duration of baldness from chemotherapy. As of now, there are no known treatments that can prevent baldness from chemotherapy.