It’s good that you’re investigating this with a magnetic camera so that you can see if it’s a disc fracture that causes the pain down the leg. Parkinson’s can actually cause neuropathic pain, and in such cases, for example, gabapentin can help. Unfortunately, however, it’s common for side effects just like you describe, so it’s a balance between adequate effect and acceptable side effects. Gabapentin doesn’t affect Parkinson’s drugs. There are other drugs for nerve pain, but it can also be valuable to get advice from a physiotherapist. /Dagholm