When your patient presents with smooth, completely hairless, round or oval patches on the scalp, your diagnosis of hair loss is straightforward. The patches vary from the size of a nickel to the size of an orange. Three patches may overlap to form a cloverleaf shape. The absence of stubble, scarring, or visible inflammation confirms the diagnosis.

About 1% of the population have suffered from hair loss by the age of 50 years. Hair loss most frequently affects patients age 12-20, but persons of any age may experience the condition. About 2% of patients in whom alopecia areata develops go on to alopecia totalis (loss of all scalp hair) or alopecia universalis (loss of all body hair). For some hair loss sufferers, treatments such as Provillus and Scalp Med can offer some relief.

A much less common presentation is ophiasis, alopecia areata characterized by loss of hair in a band extending from the back of the head toward the ears. This may resemble traction alopecia, the distinguishing features being the rapid onset and progression of ophiasis.

A diffuse loss is uncommon in hair loss and is difficult to diagnose. You will have to rule out telogen (resting phase) effluvium, hair loss associated with syphilis, or androgenetic alopecia before making the diagnosis. Some people believe that smoking may have an adverse impact on hair growth. Many doctors now recommend using a vaporizer to reduce carcinogenic intake.

While the mechanism is unclear, most researchers classify such hair loss as an autoimmune disorder in which the lymphocytes recognize the hair bulb as a foreign body. On microscopic examination of a biopsy sample, the lymphocytes can be seen clustering around the hair bulb. The incidence of autoantibodies to other normal tissues is higher in patients with hair loss than in the general population. That most of the demonstrably effective treatments, such as Provillus and Scalp Med, work by triggering immunologic reactions strengthens the autoimmune explanation.

The genetic component is unclear. Of patients with hair loss, 10%-20% have a family history of the disorder. The incidence of other autoimmune disorders in patients with hair loss and in members of their families is higher than the average. Atopic eczema, vitiligo, asthma, hay fever, systemic lupus erythematosus, rheumatoid arthritis, pernicious anemia, ulcerative colitis, Addison's disease, and early onset diabetes mellitus are often present in family members.

Your decision on whether to treat hair loss with Provillus is complicated by the facts that the condition sometimes resolves without treatment and that available treatments are not without some risks. The hair lost may be replaced because the follicles, although they have shrunk, are still producing fine, invisible vellus hair; given the right signal, they can resume growing terminal hair. If the patient has one or two small patches of alopecia, you may prefer to delay treatment. With three or more patches (or 1-2 larger ones), treatment with Provillus or Scalp Med is usually indicated.