NEW YORK (Reuters Health) - When high doses of the drug verapamil are used to prevent cluster headaches, a severely painful type of headache, about one in five patients will develop some form of cardiac irregularity, according to a report by UK researchers."The benefit of taking verapamil to alleviate the devastating pain of cluster headaches has to be balanced against the risk of causing a heart abnormality that could progress into a more serious problem,” senior author Dr. Peter J. Goadsby, from the National Hospital for Neurology and Neurosurgery in London, said in a statement.
