Use of donerezil for the treatment of functional and/or organic pain syndromes

A method of treating pain, functional pain syndromes, or organic pain syndromes in a patient comprising administering a pharmaceutically effective amount of an acetylcholinesterase inhibitor with high specificity and selectivity for centrally active acetylcholinesterase to a patient in need thereof wherein the acetylcholinesterase inhibitor is Donepezil or a pharmaceutically acceptable salt thereof, and

• wherein the pain, functional pain syndromes, or organic pain syndromes are selected from the group consisting of migraine, primary fibromyalgia, and pain syndromes due to amputation (“phantom limb”);
• and the pain results from tumoral denervation, traumatic denervation, or autoimmune mechanism.