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The following was copied - for your information - from: http://pharminfo.com/pubs/msb/pk_meto.html which contains: <<<Metoclopramide is a dopamine antagonist approved for treating gastroesophageal reflux and disorders of gastric emptying (such as diabetic gastroparesis) and for preventing chemotherapy-induced nausea and vomiting. Since it blocks dopamine receptors in the brain, metoclopramide would be expected to cause extrapyramidal (parkinsonian) side effects. Yet according to the manufacturer, at usual daily doses of 30-40 mg, parkinsonism occurs only rarely (0.2%), most often in children and young adults. Recently Avorn et al published the results of their study of medication use in 17,000 elderly medicaid patients. They found that elderly patients who were using metoclopramide for gastric problems were three times more likely to begin taking drugs specific for Parkinson's disease (levodopa) than patients who were not on metoclopramide. The risk of developing parkinsonian symptoms increased with increasing doses of metoclopramide (to a five-fold increase in patients taking more than 20 mg/day.) These results suggest not only that metoclopramide induces parkinsonism more often than previously suspected, but also that physicians may be misdiagnosing patients with parkinsonism and prescribing drugs for Parkinson's disease, rather than looking at medication history to rule out drug-induced parkinsonism. (Avorn J et al. JAMA 1995;274:1780-1782.) Parkinson's disease and parkinsonism are fairly common in older people, and may be even more common than suspected. Bennett et al conducted a community study of common health problems in the elderly, and found parkinsonian signs in a substantial number of people over age 65. A total of 464 patients underwent structured neurological examinations, neuropsychological performance testing, and laboratory testing. In addition, medications were identified, medical history taken, and an interview conducted. Almost 15% of those surveyed in the age group 65-74 had two or more signs of parkinsonism -- bradykinesia, gait disturbances, rigidity, and tremor -- while 29.5% of those aged 75-84 had parkinsonism, and 52.4% of those 85 and older had parkinsonism. Adjusted for age and sex, patients with parkinsonism had twice the risk of death of patients without symptoms of Parkinson's disease, particularly when a gait disturbance was present. (Bennett DA et al. N Engl J Med 1996;334:71-76.) It would be interesting to find out how many patients with parkinsonism were taking drugs that could induce such symptoms.>>>> I agree with this last question! -- ron 1936, dz PD 1984 Ridgecrest, California Ronald F. Vetter <[log in to unmask]> http://www.ridgecrest.ca.us/~rfvetter