Levodopa availability improves with progression of Parkinson’s disease

• Published in: Journal of neurology Vol. 253; no. 9; pp. 1221 - 1226
• Main Authors: Woitalla, Dirk, Goetze, Oliver, Kim, Jeong I., Nikodem, Alice B., Schmidt, Wolfgang E., Przuntek, Horst, Müller, Thomas
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.09.2006; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Analysis of Variance; Antiparkinson Agents - blood; Antiparkinson Agents - therapeutic use; Area Under Curve; Biological and medical sciences; Chromatography, High Pressure Liquid; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Disease Progression; Drug toxicity and drugs side effects treatment; Female; Humans; Levodopa - blood; Levodopa - therapeutic use; Male; Medical sciences; Middle Aged; Neurology; Parkinson Disease - blood; Parkinson Disease - drug therapy; Parkinson's disease; Pharmacology. Drug treatments; Severity of Illness Index; Statistics as Topic; Time Factors; Toxicity: nervous system and muscle; Nervous system diseases; Parkinson's disease; Parkinson disease; neurodegeneration; progression; Gastrointestinal; Cerebral disorder; gastrointestinal absorption; Central nervous system disease; Degenerative disease; Levodopa; Pharmacokinetics; Extrapyramidal syndrome
• ISSN: 0340-5354; 1432-1459
• DOI: 10.1007/s00415-006-0207-y

Previous pharmacokinetic trials with standard levodopa formulations showed a different behaviour of levodopa degradation in plasma of patients with Parkinson's disease (PD) in various stages. To investigate associations between levodopa plasma levels in relation to the scored intensity of PD. We administered water soluble 100 mg levodopa and 25 mg benserazide to 50 PD patients, taken off medication for at least 12 hours, and assessed the levodopa plasma concentrations during an 180 minutes period under standardised conditions. The computed area under the curve (AUC) values of levodopa plasma levels were significant higher in advanced PD patients. PD rating scores significantly correlated to the AUC outcomes and the maximum levodopa plasma concentration. Levodopa availability improves with progression of PD. This may result from deteriorated peripheral activity of levodopa metabolising enzymes or an increasing enteric dysfunction with subsequent better duodenal levodopa absorption or both.