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Protein intake and treatment of Parkinson's disease with levodopa.

Mena I; Cotzias GC
N Engl J Med 1975 Jan; 292(4):181-184
Some patients with Parkinson's disease reported a phenomenon following ingestion of a high protein meal which was similar to that which occurred following treatment with levodopa. Four groups of patients were studied: eight patients treated with levodopa continuously for at least 30 months; seven patients, five of whom were included in group 1, kept on a restricted protein diet for 2 months to 1 year; 17 patients in which serum levels of growth hormone were followed for 8 to 24 hours; and 15 patients studied to determine total body calcium. The results of the study indicated that the diet supplying the lowest protein intake tended to even out the differences in symptomatic control between morning and afternoon that were present with the average protein intake of 1.0 grams/kilogram/day. The highest protein intake exaggerated these differences. The diminution of therapeutic control appeared 1 hour after a high protein lunch and lasted throughout the afternoon. Of the five patients with greater neurologic instability, four gained their greatest stability on restricted protein intakes. Patients removed from levodopa for 1 week demonstrated almost constant levels of growth hormone with a few minor rises mostly at night. The six patients receiving levodopa in optimal amounts had mean serum concentration of growth hormone significantly higher on the diet containing 1 gram/kilogram as opposed to the diet containing 2 grams/kilogram/day of protein. The findings confirmed that a high protein meal can block the effects of levodopa in some patients with Parkinson's disease. The regimen with the most positive effects included levodopa, a peripheral decarboxylase inhibitor, and a protein intake of 0.5 grams per kilogram per day.
Protein-chemistry; Medical-treatment; Neuropathology; Nervous-system-disorders; Dietary-effects; Hormone-activity
Nuclear Medicine Pan American Hlth Organization 525 23Rd Street, N W Washington, D C 20037
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Journal Article
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Other Occupational Concerns; Grants-other
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New England Journal of Medicine
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Pan American Health Organization, Washington, Dist of Col
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division