Loss of Weight/Parkinson's

I was diagnosed with Parkinson's in 1996. Since that time, I have lost 56 pounds. My present weight is 119.

I have tried several supplements, high protein drinks, etc but have been unable to gain any weight.

Does anyone have any suggestions? I have asked several
doctors but they have no answers.

I am 5' 11 inches so I am quite thin. Your ideas/directions appreciated. Thanks

P.S. My weight has remained at 119 for the past 6 months or so.