 |
|
Metabolism of Levodopa in Patients With Parkinson's DiseaseRadioactive and Fluorometric Assays
John P. Morgan, MD;
Joseph R. Bianchine, MD;
Herbert E. Spiegel, PhD;
Leonor Rivera-Calimlim, MD;
Roscoe M. Hersey
Arch Neurol. 1971;25(1):39-44.
Abstract
The distribution of carbon 14 labeled levodopa and its metabolites was examined in six patients with Parkinson's disease after oral dosage. Levodopa is well absorbed giving maximum plasma concentrations one to two hours after dosage. Measurable levodopa is in plasma for four to six hours after a single dose. At maximum levels, however, levodopa constituted only 10% of plasma radioactivity. Small amounts of radioactivity were found in the cerebrospinal fluid two hours after dosage (partly as homovanillic acid), while 85% of the dose was recovered in urine in 24 hours. Less than 1% of the dose is recovered in the urine as unchanged levodopa. Simultaneous feeding of milk to one subject apparently delayed absorption of levodopa and may have allowed more extensive degradation of the drug in the gastrointestinal tract.
Author Affiliations
Baltimore; Nutley, NJ; Baltimore
From the Division of Clinical Pharmacology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore (Drs. Morgan, Bian-chine, Rivera-Calimlim, and Mr. Hersey), and Hoffman-La Roche Inc., Nutley, NJ (Dr. Spiegel).
Footnotes
Accepted for publication Dec 10, 1970.
Reprint requests to Department of Pharmacology and Toxicology, University of Rochester School of Medicine and Dentistry, 260 Crittenden Blvd, Rochester, NY 14620 (Dr. Morgan).
 CiteULike  Connotea  Delicious  Digg  Facebook  Reddit  Technorati  Twitter
What's this?
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
Prolonged Serum Levodopa Levels With Controlled-Release Carbidopa-Levodopa in the Treatment of Parkinson's Disease
Hutton et al.
Arch Neurol 1988;45:55-57.
ABSTRACT
Amine Precursors and Depression
Mendels et al.
Arch Gen Psychiatry 1975;32:22-30.
ABSTRACT
|
