One of the problems with levodopa/carbidopa (hereafter called simply "levodopa") is that the drug's short half-life means that it is difficult to get constant levels in the brain. In the first few years after diagnosis this has a limited impact because there are enough surviving dopaminergic neurons to provide a limited reservoir of dopamine (in vesicles) and also to provide a limited endogenous supply of dopamine. Together these mechanisms help smooth out the supply. However, as the disease progresses these safeguards diminish. This leads to pulsatile levels: when the instantaneous supply is too low the PwP is slow and stiff, when the supply is too high there is the danger of dyskinesias.

There is a need, therefore, for a control system that monitors dopamine levels in the brain and releases levodopa in the right amount and at the correct time to reach the brain as required.

I want a practical system:
- one that is non-invasive;
- one that uses bog standard levodopa, taken orally though, perhaps, dissolved in water;
- one that is cheap (no more than $50);
- one that integrates well with my present drug regime.
- one that is available in a few months.

This is what such a system could look like:

1. Start day with a normal dose.

2. Electronics monitors body response every minute, say.

3. Electronics, taking into account recent doses that may still be in the system and previous history, estimates body responses in the next hour, say.

4. If body function is likely to be OK, go to 2.

5. If not, advise taking mini dose (10mg, say).

6. Go to 2.

This is never going to be perfect because gastric emptying times vary and protein levels vary, but, in my opinion, there's a good chance that it would be better than keeping religiously to a fixed schedule of fixed doses.

You will note that it is not intended to measure dopamine levels directly. Rather, some proxy will be used, for instance blink rate or blood pressure variability.

I'll be interested to hear your comments.

John