Sunday, January 24, 2010

Morphine delays wound healing and increases infection risk

Morphine use and abuse is now found to delay wound healing in the presence of infection because it blocks the release of immune cells. Patients who use morphine for treatment of chronic pain or those abuse opiods are also at increased risk for developing infection from the effect of morphine on delayed healing

Researchers studied the effect of morphine on wound closure in a mouse model of chronic morphine use and abuse, finding that morphine inhibited the release of immune cells, and suppressed the formation of new blood vessels at the wound site. The result of the effect of morphine was inadequate wound healing and increased risk of infection from lack of clearance of bacteria from the site.

Chronic morphine users have been found to have wounds that don’t heal. The reasons are now clearer, and also have implications for evaluating the use of morphine for pain relief among specific populations as well as changes in care practices in individuals who abuse opiods.

The research was led by led by Dr. Sabita Roy at the University of Minnesota. The team of researchers concluded, that “these studies provide an in vivo tool by which further mechanistic experiments can be performed to address why, clinically, heroin-addicted patients often present with infected non-healing wounds. Understanding these underlying mechanisms affords improved treatment options not only for chronic morphine users and abusers, but can also have translational implications for immuno-compromised populations such as the elderly or those who are chronically stressed."

Morphine acts on the central nervous system and can provide analgesia and comfort. It is also frequently abused. The new finding, published February 2010 in The American Journal of Pathology shows that morphine delays wound healing and increases the risk of infection.

Am J Pathol 2010, 176: 786-799