PPI forever???

I have gastroparesis of unknown origin.   Upper and lower endoscopy essentially benign.    Mild espohagitis, this was while on a PPI.   Rarely get classic heartburn sx's.   Sometimes weakness and dizziness, sometimes chest pain, sometimes both.   Cardiology assures me not cardiac in nature.    Have had Echo, Stress, Tilt ( one came back borderline + and a second one -).   2 neg brain MRI's over the last 10 years spine negative as well.   On PPI's for many years....I go off and get really sick again.    Is this safe?    I also take reglan PRN but try to avoid it as it raised a prolactin level to 165 ( hence one of the brain MRI's)  off the med it came back down.    So my questions are 1) are long term use of PPI's safe and do you need to moniter with any bloodwork etc. and 2) is gastorparesis becoming more common, what causes it?  I'm not diabetic.

40 year old female, BMI 26 ish....No other diagnoses.....

Thanks