Botulinum toxin, a neurotoxic protein that is more commonly known as botox, is produced by the bacterium Clostridium botulinum. This toxin has many uses including both cosmetic and noncosmetic. Botox procedures do not require anesthesia and usually take just a few minutes to perform. The protein is injected into the muscle using a fine needle in order to minimize discomfort and maximize accuracy. For cosmetic procedures, a study published in Dermatologic Therapy found that men need a higher dose of Botox than women. Botox relaxes the contraction of muscles by blocking nerve impulses. The result is that muscles that can no longer contract and the wrinkles relax and soften. It usually takes two to four days to see cosmetic improvement and the effects tend to last from four to six months. Most patients require retreatment to remove wrinkles and lines as they begin to reappear, but after each injection the wrinkles return as less severe as the muscles are trained to relax. It is used cosmetically to fix moderate to severe brow furrow, uncontrolled blinking, lazy eye, wrinkles, and facial creases. These procedures use a small amount of diluted botulinum toxin that enables controlled weakening of muscles. In addition to cosmetic use, Botox is used to treat cervical dystonia, writer's cramp, excessive sweating, achalasia (an esophagus problem), chronic pain, neuropathy, bladder control problems, and migraine headaches. Some studies have indicated that Botox used for aesthetic purposes can also help people with mental illness. A study published in Dermatologic Surgery found that treating clinically depressed patients with Botox on the frown lines of their faces actually rid them of their depression.