Have you tried fava beans?? If you are into natural medicine, as I am, the favas may be just the thing for you. Check post :Four Acres for favas to grow on. It has all about what I do naturally for my PD symptoms prayers, Aunt Bean

While I was finding the correct dosage for me I experienced nausea the first two weeks as well as each dose increase. It did pass for me now that I am on a steady dose. I also found that mucuna pruriens makes me nausea as well.

I have an acquaintance that swears by puffing a bit of cannabis for his nausea. He also puffs a bit for his overall symptoms of nausea, rigidity, pain and depression. He swears by it. He still needs his Sinemet but swears that it hammers all of the other symptoms and requires less of a dose as well.