Pain killers, which are used widely all over the world to obtain relief from pain, are very effective in pain relieving properties but cause certain undesirable side effects such as itching. This side effect is seen when opiates, morphine and oxycodone are used. The itch has been one of the most intriguing questions that scientists and researchers have faced. The scientific community remains clueless about the cause of the itch. However, latest research by scientists of St. Louis Washington University of Medicine has revealed a way of controlling the itch without causing any change in the healing and pain relieving properties of drugs.The new discovery can be used to provide relief to people who have to use pain killers regularly, who undergo treatments for cancers and pregnant women, who are administered painkillers to ease labor pains. The study was conducted at the newly established Center for the Study of Itch at Washington University.

The director of the institute, Prof Chen, said that a novel method to prevent itching that results from painkillers has been found. The research team identified a opium receptor that is responsible for the itch and blocking this receptor can be a solution to stop the itching. He also assured that the pain killing property of the pain killers will remain intact. This receptor is named MOR1D. The study was conducted on mice and it was found that when MOR1D was blocked, mice remained free of itch. It was also found that the pain relief that the mouse received was still optimum.

There is another receptor called GRPR, which was discovered by Prof. Chen that transmits the itching from one neuron to another. During the course of the present study, it has been found that MOR1D triggers GRPR and causes propagation of the itch. According to Prof Chen, human body triggers GRPR in different ways in order to propagate itch. Xian-Yu Liu, the first author of the study and a post doctoral researcher, found another variant of opioid called MOR1 that is directly responsible for propagating the painkilling sensation in the spinal cord. Interesting results were found when MOR1 was blocked. The mice did not receive any pain killing benefit from drug but the itching persisted. Chen said that this research is profound because it has zeroed in on the specific receptor, MOR1D, which causes the itch without causing any effect on pain killing properties. Blocking it ought to effectively solve the problem.