Sex is an excellent method of pain relief, whether you have it alone or with a partner. Although it may be one of the first things to disappear when you are in constant pain, the good news is your sex drive can be kept healthy by regular ... ehem... practice. Keeping sex enjoyable also when you have daily pain takes some time, effort and creativity, but it's definitely worth it, because apart from everything else good about it, orgasm is a powerful pain-killer!
Oxytocin, a natural chemical in the body that surges before and during climax, gets some of the credit, not to mention the amount of endorphins produced. At the risk of repeating myself here: Endorphins (a neurotransmitter in the brain) as a painkiller are much more powerful than morphine. Around twenty different types of endorphins have been discovered in the nervous system to date. One of the endorphins, beta-endorphin, is 18-50 times more effective than morphine, while another, called dynorphin, is over 500 times stronger!
Besides that, there's science showing that having sex raises your pain tolerance. A study by Beverly Whipple, professor emeritus at Rutgers University and a famed sexologist and author, showed that when women had an orgasm “the pain tolerance threshold and pain detection threshold increased significantly by 74.6 percent and 106.7 percent respectively.”
So why wait?