Morphine....where has my mam gone

Hi all

My mam.stsrted slow release morphine tablets after tramadol was not helping with back pain .fast forward 3-4 weeks and my mam is In such a state .her eyes are constantly In the back of her head,she's hallucinating,she basically a different person .is this normal with morphine??my dad has asked Macmillan nurse who advised mam stays on them.its heartbreaking to see her like this

Many thanks

Nicola