Does Parkinson's Cause Neuropathy?

The short answer to this question is yes. Parkinson's Disease has been known to result in a form of peripheral neuropathy (PN). PN is typically associated with diabetes mellitus (DM), but it can happen with Parkinson's even without the presence of DM. Why does this happen? Let's discuss briefly...

Many physicians may dismiss this question, but a well trained neurologist and/or movement disorders specialist should immediately recognize that there could be a connection between neuropathy and PD. The symptoms of neuropathy include tingling, burning, numbness, and pain in the hands, feet, or both. Peripheral neuropathy in PD is actually distinct from diabetic neuropathy in that with DM the damage done to nerves is due to high blood sugars and resultant fatty infiltrates that damage the blood vessels that feed the nerves. With Parkinson's Disease there is no known mechanism; however, there is a correlation between Parkinson's related neuropathy and deficiencies in Vitamin B6 and Vitamin B12. Why are these important? B6 is directly responsible for the health of nerve cells in the brain, spinal cord, and peripheral nerves. B12 not only helps B6 to do this job, but is also responsible for the health of myelin sheath building and maintenance. For a reminder of why myelin sheaths are important, just think Mutiple Sclerosis (MS). MS is a demyelinating disease, which results in nerve conduction becoming faulty and in some instances unable to happen at all. Specific supplemental treatment with these vitamins* can reduce the pain, numbness, and tingling that can come with neuropathy when in conjunction with PD and could help prevent the worsening of the symptoms. *Please NOTE: Vitamin B6 should not be taken when on Levodopa ALONE, but is safe with Carbidopa/Levodopa (Sinemet). 

This next bit is speculation on my part, but knowing what we know about PD and the gut-brain connection it makes me wonder if the connection between PD and vitamin B6 and B12 deficiency could be some form of absorption disorder in the gut that is associated with PD. If adequate gut health and normal flora of bacteria spell warding off such diseases as Parkinson's, then perhaps the opposite means higher likelihood of developing PD and also vitamin absorption issues? Recent research studies have suggested the possibility of such connections between the gut and developing PD, such as this one at University of Florida. 

The bottom line is that the treatment for B6 and B12 deficiencies is relatively non-invasive and your PCP and neurologist should be able to help you to come up with solutions for dealing with this moving forward.