What is pain?
Pain starts in receptor nerve cells found beneath the skin and in organs throughout the body. When you are sick, injured, or have other type of problem, these receptor cells send messages along nerve pathways to the spinal cord, which then carries the message to the brain. Pain medicine reduces or blocks these messages before they reach the brain.
Pain can be anything from a slightly bothersome, such as a mild headache, to something excruciating and emergent, such as the chest pain that accompanies a heart attack, or pain of kidney stones. Pain can be acute, meaning new, subacute, lasting for a few weeks or months, and chronic, when it lasts for more than 3 months.
Chronic pain is one of the most costly health problem in U.S. Increased medical expenses, lost income, lost productivity, compensation payments, and legal charges are some of the economic consequences of chronic pain. Consider the following:
Low back pain is one of the most significant health problems. Back pain is a common cause of activity limitation in adults.
Cancer pain affects most people with advanced cancer.
Arthritis pain affects more than 50 million Americans each year.
Headaches affect millions of U.S. adults. Some of the most common types of chronic headaches are migraines, cluster headaches, and tension headaches.
Other pain disorders such as the neuralgias and neuropathies that affect nerves throughout the body, pain due to damage to the central nervous system (the brain and spinal cord), as well as pain where no physical cause can be found–psychogenic pain–increase the total number of reported cases.