Has it been suggest that you have your gall bladder removed? Has anything else been suggest as a cause of your GI symptoms?
Dopamine receptors respond to dopamine and if they are blocked the response would not occur. This is just a theory, not really substantiated as yet. I don't think there's any correlation with the CRPS or the medications. Bottom line here--even if a cause were found, I don't think there's any way to restore the normal function to your gall bladder.