Sebum is a normal product of certain skin glands. In seborrhea, excessive sebum is produced and appears as dry, light-colored flakes in the hair coat or as greasy, waxy scales on the skin and hair. Because sebum is a fatty material, it becomes rancid and causes a strong coat odor.

Seborrhea may occur as a disease by itself (primary seborrhea) or result from an underlying disease (secondary seborrhea). While secondary seborrhea often clears up when the underlying disease is cured, primary seborrhea is a chronic disease that may be controlled but not cured. The cause of primary seborrhea is unknown.

Treatment: Anti-seborrheic shampoos must be used on a regular basis to remove accumulated sebum, prevent skin irritation and control odor. Treatment must be tailored to the individual patient.