Also, in cases of chronic pain, some doctors may prescribe Amitriptyline as a sort of pain killer, operating on the assumption that an elevated mood may increase one's pain threshold. It won't actually relieve the pain you're suffering, but will make you better equipt to deal with it. I was prescribed a daily dose of Amitriptyline after years of suffering with a herniated disc. It made me very very drowsy, and was all but ineffective as a pain killer.