Rick: See below from an earlier posting. You can reduce mucuna dose dramatically with same effect if taken with reduced amount of sinemet

"But that's not the whole story: the enzymes which greet levodopa as it enters the brain have some identical twins in the bloodstream outside the brain. Levodopa which gets converted to dopamine in the peripheral bloodstream (that is, outside the brain) is of no use to the brain. The presence of these enzymes in the peripheral system means that for every molecule of levodopa that makes it to the BBB unchanged, there are many more that get converted to dopamine and get turned away. This creates a problem. You have to take a whack of levodopa in order for a sufficient dose to enter the brain. And then there's all that excess dopamine in the peripheral bloodstream looking for a home. Some of it can be used by your kidney; some can be used for regulating blood flow. The rest will cause nausea, vomiting and general unpleasantness.

Enter carbidopa. It acts as a bodyguard for levodopa, keeping enzymes at arms length. It does this well enough to allow five times as much levodopa to reach the brain. At the BBB, carbidopa gets turned away. This is convenient because once levodopa enters the brain we don't want carbidopa present to protect levodopa from the enzymes which will convert it to dopamine. When levodopa and carbidopa are taken together, a much higher percent of the levodopa reaches the rain. So the amount of levodopa taken can be reduced accordingly; this, in turn, prevents side effects by reducing the amount of excess dopamine in the peripheral bloodstream.

All levodopa pills come with enough carbidopa (or a similar drug) to protect the levodopa during its trip through our digestive system and bloodstream to the brain. Carbidopa is never 100% effective in its bodyguard action but it makes a big difference in the amount of levodopa that makes it to the brain.

Fava and mucuna beans do not appear to contain anything corresponding to carbidopa. From a medicinal point of view, the lack of carbidopa in the beans creates a problem. For an adequate dose of levodopa to reach the brain, a lot of beans have to be eaten. This is unhealthy, both because of the large amount of levodopa that gets converted to dopamine in the peripheral system and because beans typically contain small amounts of toxins. Bean toxins don't cause any difficulty if the beans are just eaten occasionally or in small amounts. But frequent meals of large helpings of beans would not be healthy.

In the USA, carbidopa is available by itself (under the trade name Lodosyn). Because it is a specialty item, it costs twice as much as a levodopa pill which has the same amount of carbidopa plus the levodopa. In Canada, Lodosyn is not an approved drug. So taking a Lodosyn pill with a small helping of beans is not an option.

At present, I have a prescription for 25 mg Carbidopa/ 100 mg Levodopa. Sometimes I just take the pill. But whenever convenient, which is most of the time, I break a pill in half and eat enough fava bean sprouts or mucuna bean powder to provide the other 50 mg levodopa. My assumption is that the bean levodopa will be able to piggy back on the carbidopa from the pill. Also, I know I am getting 50 mg levodopa from the pill so if my estimate of the levodopa content of the beans is a little off, the total error is less than it would be if I relied entirely on the beans. So far, this is working very well. But I'm in the early stages of PD and my system is more adaptable than it will be 10 years from now. "