Sympathetic blocks can also alter the function of organs that have a sympathetic control component...
However, surgical sympathectomy may result in a compensatory hyperhidrosis: a condition characterized by abnormally profuse sweating in a location remote form the sympathectomy. Other complications can also occur, including paresis, paralysis, and bowel or bladder dysfunction. Neurolytic procedures typically can only be considered if all other measures have failed.
http://www.wipo.int/pctdb/en/wo.jsp?IA=WO2005072433&wo=2005072433&DISPLAY=DESC