Comparison of motor response to apomorphine and levodopa in Parkinson's disease. (65/147)

The magnitude and pattern of motor responses to single doses of subcutaneous apomorphine and oral levodopa were compared in 14 patients with Parkinson's disease. Although apomorphine produced much shorter motor responses than levodopa, the quality of response to the two drugs was virtually indistinguishable. These clinical observations support the notion that integrity of striatal post-synaptic dopamine receptors is a key determinant of responsiveness to dopaminergic treatment in Parkinson's disease.  (+info)

Diurnal differences in response to oral levodopa. (66/147)

Diurnal differences in duration and quality of motor response to levodopa are frequently described by patients. The quality and duration of motor responses were objectively assessed to morning and afternoon oral levodopa doses in five patients with Parkinsonian motor fluctuations who complained of diurnal variation in response to their normal levodopa medication. Results suggest that under controlled conditions which eliminated the effects of diet and overlapping levodopa effects the response to levodopa remained unchanged throughout the day, and that the duration of response could be predicted by plasma levodopa levels.  (+info)

Sinemet-ferrous sulphate interaction in patients with Parkinson's disease. (67/147)

1. This study examined the effects of administering ferrous sulphate 325 mg with Sinemet (100/25 tablet) on levodopa and carbidopa bioavailability and on signs of Parkinson's disease in nine patients. 2. Ferrous sulphate ingestion with Sinemet resulted in a decrease in levodopa area under the curve (AUC) of 30% (P less than 0.01) and a greater than 75% decrease in carbidopa AUC. Despite a strong relationship between reductions in levodopa AUC and reductions in Sinemet efficacy (r = 0.83, P less than 0.01), the average reduction in Sinemet's efficacy associated with ferrous sulphate did not achieve statistical significance (P = 0.055). 3. Chemical studies indicate that iron forms chemical complexes with carbidopa in a similar manner to levodopa and is a likely mechanism for the drug interactions. 4. AUC when a Sinemet tablet is taken concurrently with a ferrous sulphate tablet appears to be clinically significant in some but not all patients. The clinical significance of repeated ingestion of ferrous sulphate with Sinemet requires further studies.  (+info)

Beneficial effects of natural phenolics on levodopa methylation and oxidative neurodegeneration. (68/147)

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Pharmacokinetics of levodopa, carbidopa, and 3-O-methyldopa following 16-hour jejunal infusion of levodopa-carbidopa intestinal gel in advanced Parkinson's disease patients. (69/147)

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Severity of Parkinson's disease is a risk factor for peak-dose dyskinesia. (70/147)

Fifty four patients with idiopathic Parkinson's disease receiving levodopa therapy were studied. Thirty three of these patients displayed peak-dose dyskinesia. Neither the duration of Parkinson's disease nor the duration of levodopa therapy discriminated between patients with and patients without peak-dose dyskinesia. Consequently, these criteria could not determine whether the first appearance of peak-dose dyskinesia depends on the duration of Parkinson's disease--a factor that is related to the severity of the disease--or on the duration of levodopa therapy. A subgroup of nineteen patients with unilateral or unequivocally asymmetrical peak-dose dyskinesia was examined 12 hours after withdrawal of levodopa. A levodopa testdose provoked unilateral or unilateral preponderant peak-dose dyskinesia which always involved the most severely affected side and which also happened to be the side of onset of the disease. This demonstrates that the severity of Parkinson's disease is the main risk factor for peak-dose dyskinesia.  (+info)

Levodopa-carbidopa intestinal gel in advanced Parkinson's disease open-label study: interim results. (71/147)

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Selecting deep brain stimulation or infusion therapies in advanced Parkinson's disease: an evidence-based review. (72/147)

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