Alopecia is a condition that causes hair loss on some or all areas of the human body—most commonly the scalp. Generally considered to be an autoimmune disorder, alopecia causes the body to undermine the health of its own hair follicles. It usually afflicts those people who have a genetic predisposition to hair loss, but it has also been linked to people who have autoimmune diseases in their family tree. Many believe that environmental conditions—particularly stress—combine with genetics to trigger alopecia.

In its initial stage, alopecia causes as a bald spot on the scalp. In few cases, alopecia does not progress and lost hair grows back months later. In rare cases, alopecia can bloom into alopecia totalis, which causes hair loss throughout the scalp, or alopecia universalis, which results in hair loss over the entire body.

The following are other, less common forms of alopecia:

• Diffuse Alopecia Areata: Hair loss in patches throughout the scalp.
• Alopecia areata monolocularis: Baldness in one specific area
• Alopecia areta multilocularis: Baldness throughout many areas of the head.
• Alopecia areata barbae: Hair loss on the face (beard)
• Toxic alopecia: hair loss following fever or illness. (Certain medications, such as thallium and retinoids, can also trigger this condition.)
• Scarring alopecia: Scars from burns or injuries can stop hair from returning. So can scarring from diseases and disorders like lupus, tuberculosis, and skin cancer.

The effects of alopecia can be more than cosmetic. Loss of hair on the scalp leaves the remaining hair less protected—and more prone to burning in the sun. Alopecia can also affect mental health by undermining the patient’s self-image. Many who deal with alopecia often develop social phobias, anxiety, and varying degrees of depression.