http://www.functionalps.com/blog/201...nsons-disease/

"Abstract

AIMS:

Although it is commonly recognised that diseases of the thyroids can simulate extrapyramidal disorders, a review of the causes of Parkinsonism in the neurology literature shows that they are not usually mentioned or, if so, only very briefly. The development of hypothyroidism in a patient with Parkinson s disease can go undetected, since the course of both diseases can involve similar clinical features. Generally speaking there is always an insistence on the need to conduct a thyroidal hormone study in any patient with symptoms of Parkinson, but no emphasis is put on the need to continue to rule out dysthyroidism throughout the natural course of the disease, in spite of the fact that the concurrence of both pathological conditions can be high and that, in the same way hypothyroidism can simulate Parkinson s disease, the latter can also conceal hypothyroidism.

CASE REPORT:

We report the case of a female patient who had been suffering from Parkinson s disease for 17 years and started to present on off fluctuations that did not respond to therapy. Hypothyroidism was observed and the hormone replacement therapy used to resolve the problem allowed the Parkinsonian fluctuations to be controlled.

CONCLUSIONS:

We believe that it is very wise to suspect hypothyroidism in patients known to be suffering from Parkinson s disease, and especially so in cases where the clinical condition worsens and symptoms no longer respond properly to antiparkinsonian treatment. These observations stress the possible role played by thyroid hormones in dopaminergic metabolism and vice versa.

http://www.ncbi.nlm.nih.gov/pubmed/12402227"

If your blood tests are normal try the Barnes basal temperature test. Unusually low temps < 97.8 may indicate subclinical hypothyroidism. Dr. Mark Starr, "A host of other problems have been linked with hypothyroidism. In Dr. Barnes' opinion, 99 times out of 100, when a low basal temperature is associated with an illness, a trial of thyroid medication is called for. I agree completely."


http://www.youtube.com/watch?v=2FVNgYHLeYs

Thyroid drives the dopaminergic system which in turn drives the liver's cytochrome P-450 detoxification function (also found in the brain.) The detox system has pathways that deal with different biotransformations of toxins (xenobiotics) and these vary genetically. PWP's e.g. have very weak sulfation detox potential. It seems to go in a vicious circle as more toxins affect the dopaminergic brain which in turn lessens the liver and brain's detox function:

""And some of these substances that rely on the so-called sulfation pathway to be broken down and eliminated can be highly toxic. Studies are now proving an association between dysfunction of this sulfation pathway and a host of illnesses including Alzheimer's, Parkinson's, autism, rheumatoid arthritis, food allergies, motor neuron disease, primary biliary cirrhosis, and multiple chemical sensitivity. In many people, the sulfation pathway in the liver is the weakest link in the system's chain of actions."
- Brenda Watson and Leonard Smith, The Detox Strategy: Vibrant Health in 5 Easy Steps

It might be that detoxification, thyroid hormones and sulfation enhancers like MSM, cruciferous vegetables, and sulfur amino acids (methionine, cysteine, etc.) might be beneficial.