Dear Mr/Ms Nehag
Here the constipation
problem is due to the side effect of Tab.Parkin and it is must along with Syndopa
Try decreasing the dose of Parkin and see ( Before that you talk to your treating doctor)
better go for liquid or semi liquid diet
and it should be nutritious , go for coconut water, fruits ,high fiber diet, encourage physical exercise ( walking )
It is also not advisable to put him long on Stimulant laxatives. in this case you can better consult Medical Gastroenterologist .
always keep elderly patient on as minimum drugs as possible.