This work follows on from collaborations with David Spry, David Ponsonby and others in which holistic or panaromic perspectives of Parkinson's Disease are being taken. For more background to this, please read:
Taking these ideas forward, I went on to research the linkages between histamine and dopamine, and thus began to form a picture, with the logical conclusions that allergic/inflammatory reactions and Parkinson's Disease are, indeed, very strongly linked. Here's what I uncovered (for more details and reference sources please see my research notes on this).
Histamine and the Brain
Histamine is known as substance which has a key role in allergic reactions and inflammation, and gastric process (stomach acid), but what may be less well known is that it also acts as a key neurotransmitter (like dopamine). In particular, histamine plays significant roles in arousal, the pituitary gland, appetite and cognition and is considered a "wake-promoting" substance. It may therefore also be important in sleep disorders. Histamine in the brain also plays a part in pain perception.
Stress, allergic reactions, digestion and histamine containing foods all contribute to the release of histamine. Digestion issues and food intolerances are also well known to be very prevalent in PD and also in blocking the effectiviness of Parkinson's drugs. Anyone with PD will know all about the impacts of stress.
One of the most interesting and important facts I discovered was post mortem studies have revealed that histamine concentration levels are abnormally high in the brains of those with Parkinson's Disease.
The Histamine-Dopamine Link
Furthermore, histamine also acts to control and regulate the production and release of other neurotransmitters, including dopamine. For example, medications which block histamine can increase dopamine release, while histamine also stimulates prolaction releases, known to inhibit dopamine, and the activation of histamine production in certain cell causes a decrease in dopamine production by these cells.
The Allergy-Parkinson's Link
Given the above facts, we can consider that allergic reactions will impact very strongly on Parkinson's Disease, its symptoms, and its onwards degeneration. Allergic reactions lead to high levels of histamine, which is directly related to dopamine depletion - the key issue in people with PD. As a piece of conjecture, it is not hard to make an intuitive leap that sustained allergic reactivity in the long term may cause dopamine producing cells in the brain to become dormant, or because they are not active, to die (because in the brain, "use it lose it" holds fast!)
Testing the Hypothesis
As usual, I began to self-experiment after gleaning these new understandings of my disease. I set out to minimize, as far, as possible any allergic reactions and to maximize anti-histimine effects. The things I've tried include the following: drinking lots of herbal teas with well known anti-histimine properties (I found nettle, fennel and rosemary infusions, in particular, work well); investing in red light and infrared technologies, now well proven to help in allergy relief, including a hand held infrared massager and red light nasal insert, both sold as anti-allergic devices; a meticulous and careful investigation, followed by deselection from my dietary intake, of foods to which I am sensitive, through internet researching, detailed record keeping and empirical trial and error.
For myself, these have proven the above findings about the overlaps between allergic reactions and Parkinson's Disease beyond any doubt for my own wellness, because these inventions have impacted very significantly on reducing my Parkinson's symptoms and improving my quality of life.