Pain 

Pain of such proportions overwhelms all other symptoms and becomes the problem. People so afflicted often cannot work. Their appetite falls off. Physical activity of any kind is exhausting and may aggravate the pain. Soon the person becomes the victim of a vicious circle in which total preoccupation with pain leads to irritability and depression. The sufferer can't sleep at night and the next day's weariness compounds the problem-leading to more irritability, depression, and pain. Specialists call that unhappy state the "terrible triad" of suffering, sleeplessness, and sadness, a calamity that is as hard on the family as it is on the victim. The urge to do something-anything-to stop the pain makes some patients drug dependent and drives others to undergo repeated operations or resort to questionable practitioners who promise quick and permanent "cures."

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