List friends, I want to offer a short biochemistry lesson: (from better than a decade o= f=0Amemory-don't pick me too close). My purpose is to give you a working= =0Aunderstanding of how the new medicines work. Dopamine is a chemical messenger between certain ("dopaminergic") nerve c= ells.=0AIt operates in the synapses (the tiny space that separates commun= icating=0Anerves). Between normal cells, part of that dopamine is taken up and reused by the= =0Asending neuron. Another part is destroyed. Dopamine is broken down i= n the=0Abody by two enzymes-Mono Amine Oxidase (MAO) and Catachol -O- Met= hyl=0ATransferase (COMT). General principle: when something is named an =85ase, it is an enzyme. T= hese=0Aare usually protein molecules. They often posses interesting chem= ical and/or=0Amechanical properties They operate at the molecular level. Selegiline, (Deprenyl) is a selective MAO B (for brain) inhibitor. In th= e=0Arecommended doses, it does not bother MAO A which destroys dopamine i= n=0Asynapses outside the brain. The two COMT inhibitors we have now (Tas= mar is=0Aavailable) are not selective. They decrease dopamine destructio= n in the whole=0Abody. Fortunately, there is carbidopa (blocks the enzym= e that turns levodopa=0Ainto dopamine outside the brain) in Sinemet. Thi= s prevents the accumulation=0Aof dopamine in the body outside the brain. = Thus, elevated B/P, increased=0Aheart rate and other symptoms of excess = dopamine do not have to be a problem. Summary: 1 Dopamine is broken down two ways: MAO and COMT 2 Deprenyl and Tasmar block these enzymes, respectively 3 The net effect is that of more dopamine. 4 Tasmar operates outside the brain as well as in the brain If you understand how this works you can understand how to use these new= =0Amedicines. I prefer very slow changes. Hope you find this helpful. Regards, WHH 54/18