Amitriptyline hydrochloride (Elavil^®) is a medication licensed to treat depression. This prescription drug may also be used "off-label" to relieve chronic pain and prevent migraine headaches. Other amitriptyline uses include helping to treat bedwetting, ADHD, fibromyalgia, and bulimia. It is also thought that amitriptyline may be effective at helping people quit smoking. The amitriptyline dosage your healthcare provider recommends will be based on several factors, such as your age, other existing medical conditions you have, what condition is being treated, and other medications you are taking (including vitamins and supplements).