Prominent facial lines can be misinterpreted as anger, anxiety, fatigue, or sadness, and contribute to the look of an aging face. A number of factors cause these undesirable lines, including fat atrophy, sun damage, chronic gravitational changes and hyperfunctional lines. Hyperfunctional lines are the result of muscles contracting beneath the skin, and are sometimes referred to, depending on location, as crow’s feet, lipstick lines, forehead furrows and glabellar folds (between the eyebrows.) When attempting to eliminate these wrinkles, it is important to address the underlying physiology, which means paralyzing the muscle.