Pain is felt when the message reaches the brain via the nerves and the spinal cord. The spinal cord is a sort of junction for all nervous signals to the brain. Pain-balms contain volatile oils that irritate the nerves on the skin surface. Since the messages from the skin counteract the pain message being communicated to the brain, the brain senses lesser pain than before. Muscle relaxants added to pain-balms also ease tense muscles. Massages increase blood flow to the affected areas. All these add up to a sensation of relief.
