Thanks for your query.Based on the facts that you have posted it appears that your father is known patient of Parkinson's disease taking drugs for the same.
He has frequency of micturition and his Ultrasound
study revealed mild Prostatomegaly
.and has been advised to take Raliflow.
This drug does not have severe side effects even taken for a long time.and does not have drug interaction
with anti parkinson's medicines.