Pain

   Pain is a vital part of our body's defences, and without it we could not survive.

    Pain warns us what things are dangerous, and so helps us avoid damage to our body. 
 If the body is already damaged, pain helps with healing because it makes us protect our injuries. Some babies are born with a rare condition that males them unable to feel pain. Thay do not learn the lessons that pain teaches , and as a result suffer many fractures and infections.

  Pain happens when nerve endings in our skin and our internal organs send messages through the central nervous system to our brain.The brain itself cannot feel pain. There are two types of pain - acute pain, which lasts a short time and  is removed when the cause is cured, and chronic pain ,which can last a lifetime and cannot usually be treated.Chronic pain must be managed using drugs or other methods.

   Drugs relieve pain in two ways. Some block the nerves messages and prevent them getting to the brain.. Others change the way the brain receives the messages, reducing their effect. Many methods of controlling chronic pain without drugs have been developed. These include hepnosis, acupuncture, massege and electronic stimulation of nerves.

  Pain sometimes works in strange ways. It is possible , for example, to suffer a serious injury but not feel any pain-soldiers in battle may not feel pain from wounds until after the battle. The opposite can happen too - patients who lose a limb can continue to fell pain in the limb long afterwards, even though it is missing. This 'phantom limb' pain is an example of neuropathic pain, caused by damage to the remaining nerves.