A few well-known examples are fibromyalgia, migraine headaches, and chronic back pain. Over 1.5 billion people suffer from chronic pain, including 100 million in the United States who collectively pay $500 billion per year for treatment. When you include lost productivity in the price tag, pain costs the United States $635 billion each year. It is also frustratingly hard to treat, as the currently prescribed pain medications, analgesics, are ineffective more than half the time. This worldwide epidemic of chronic pain is one of today’s great medical mysteries.21
