Is Severe Stomach Pain Common In Progressive Supranuclear Palsy Patient?

My mom age 84 has Progressive Supranuclear Palsy. She vomited up her tube feeding on Friday. She complains of stomach pain. I try giving her tube feeding and she moans. She also keeps her eyes closed.

I have been told there isn't anything you can do but make her comfortable with morphine. Is severe stomach pain common in this condition.