Since L-dopa compensates for the lack of dopamine and has an effect that alleviates tremors and stiffness and improves mobility, I wonder why joint pain and other aches and pains persist?

Joint pain and other aches and pains could be caused by factors other than Parkinson’s. Pain caused by Parkinson’s is often relieved, as you mention, by L-dopa if it is linked to muscle stiffness. However, there are also several other types of pain that can occur with Parkinson’s and which may require different kinds of treatment. Parkinson’s is not solely caused by a dopamine deficiency. Consulting a physiotherapist may be helpful in analysing the type of pain.

Dag Nyholm