Parkinsons medication side effects

I'm new to this forum but my father has suffered from Parkinsons for six years as well as low BP.

He's now got major health problems as his doctor reduced his Sinemet due to his low BP and now he's unable to swallow food. Are there any newer Parkinsons drugs out there which do not have the potential to reduce blood pressure?

Any suggestions would be gratefully received
My husband suffered from very low blood pressure when standing and was falling and fainting, when he came off DAs and went on to Sinemet.
He spent a month in hospital and was eventually given Adcal-D to raise his blood pressure.
He still takes it and the low blood pressure (79/40 for 10 mins when standing after lying down) returned to normal.We presume he will take it for ever and he feels much better.
Worth asking the doctor about it?
Good luck.