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This is part of an article on "Principal Proposed Natural Treatments" under condition Parkinson's disease. Copyright 2007 EBSCO Publishing

CDP-Choline

"Short for cytidinediphosphocholine, CDP-choline (sometimes called citicholine) is a substance that occurs naturally in the human body. It is closely related to choline, a nutrient commonly put in the B vitamin family. For reasons that are not completely clear, CDP-choline seems to increase the amount of dopamine in the brain.3,4 On this basis, it has been tried for Parkinson's disease".

In a 4-week, single-blind study of 74 people with Parkinson's disease, researchers tested whether oral CDP-choline might help levodopa be more effective.5 Researchers divided participants into two groups: one group received their usual levodopa dose, the other received half their usual dose without knowing which dosage they were getting. All the participants took 400 mg of oral CDP-choline 3 times daily.

Even though 50% of the participants were taking only half their usual dose of levodopa, both groups scored equally well on standardized tests designed to evaluate the severity of Parkinson's disease symptoms.

Support for the use of CDP-choline also comes from studies in which the supplement was administered by injection.6-9

In general, CDP-choline appears to be safe.11 The study of oral CDP-choline for Parkinson's disease reported only a few brief, nonspecific side effects such as nausea, dizziness, and fatigue.12 In a study of 2,817 elderly people who took oral CDP-choline for up to 60 days for problems other than Parkinson's disease, side effects were few and mild and reported in only about 5% of participants.13 Two-thirds of these side effects were gastrointestinal (nausea, stomach pain, and diarrhea), and none required stopping CDP-choline. The dose in this study was 550 mg to 650 mg per day, about half the dose used for Parkinson's disease".