my husband has been on oramorph and is now lie=ke a gibbering mon...

my husband has been on oramorph and is now lie=ke a gibbering monkey.He has mouth cancer and this is his pain relief afer 6 weeks of radiotheraphy.Morphine to me is given out like dooly mixtures without the information of what it can do he does not want to take it but it has taken my husband!! Health carers think pain - take morphine but it makes the whole situation worse because you do not know they are in real paind or justing affected by the morphine -does anyone know what Iam talking abut!!!!!!!!!!!!!?