Are There Any Side Effects Of Taking Finasteride?

My father is taking 5 MG of finasteride a day-with 50 mg Janvria, 20 mG Lisinopril, 40 mg simvastatin. He was doing very well for his age, he is 83 and he was able to do everything for himself until they added the finasteride to his drug list. He is urinating at night every 15-20 minutes, his legs cannot hold him up anymore, he seems incoherent at times, his fingers have shooting pains. He has fallen mulitple times trying to get to the bathroom. This downgrade has happened almost overnight. I think he is resigned to dying, but none of this makes any sense. 6 months ago, his family doctor said he would live to 100 and he is getting progressively worse EVERY DAY! Could some of this stem from the new medicine?