a-MSH is low in Chronic Inflammatory Response Syndrome (CIRS), an acute and chronic, systemic inflammatory response syndrome acquired following exposure to the interior environment of a water-damaged building with resident toxigenic organisms as well as volatile organic compounds. In CIRS, blocked leptin receptors will no longer create the initiation of steps that lead to production of a-MSH. Reduced MSH production results in yet another set of problems and symptoms. The production of melatonin is reduced which results in sleep problems. Endorphin production is suppressed which leads to chronic and sometimes unusual pain.
Lack of MSH can cause malabsorption or 'leaky gut' which further weakens and deregulates the immune system. White blood cells eventually lose regulation of cytokine response so that opportunistic infections may occur or recovery from infections is slower. Low a-MSH can cause the ability for resistant staph (MARCoNS) to survive in biofilm on the mucous membranes.