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Negida A, Hassan NM, Aboeldahab H, Zain YE, Negida Y, Cadri S, Cadri N, Cloud LJ, Barrett MJ, Berman B. Efficacy of the iron-chelating agent, deferiprone, in patients with Parkinson's disease: A systematic review and meta-analysis. CNS Neurosci Ther 2024; 30:e14607. [PMID: 38334258 PMCID: PMC10853946 DOI: 10.1111/cns.14607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 01/01/2024] [Accepted: 01/06/2024] [Indexed: 02/10/2024] Open
Abstract
INTRODUCTION Several studies have reported iron accumulation in the basal ganglia to be associated with the development of Parkinson's Disease (PD). Recently, a few trials have examined the efficacy of using the iron-chelating agent Deferiprone (DFP) for patients with PD. We conducted this meta-analysis to summarize and synthesize evidence from published randomized controlled trials about the efficacy of DFP for PD patients. METHODS A comprehensive literature search of four electronic databases was performed, spanning until February 2023. Relevant RCTs were selected, and their data were extracted and analyzed using the RevMan software. The primary outcome was the change in the Unified Parkinson's Disease Rating Scale (UPDRS-III). RESULTS Three RCTs with 431 patients were included in this analysis. DFP did not significantly improve UPDRS-III score compared to placebo (Standardized mean difference -0.06, 95% CI [-0.69, 0.58], low certainty evidence). However, it significantly reduced iron accumulation in the substantia nigra, putamen, and caudate as measured by T2*-weighted MRI (with high certainty evidence). CONCLUSION Current evidence does not support the use of DFP in PD patients. Future disease-modification trials with better population selection, adjustment for concomitant medications, and long-term follow up are recommended.
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Affiliation(s)
- Ahmed Negida
- Parkinson's and Movement Disorder CenterVirginia Commonwealth UniversityRichmondVirginiaUSA
- Medical Research Group of EgyptNegida AcademyArlingtonMassachusettsUSA
| | - Nafisa M. Hassan
- Medical Research Group of EgyptNegida AcademyArlingtonMassachusettsUSA
| | - Heba Aboeldahab
- Medical Research Group of EgyptNegida AcademyArlingtonMassachusettsUSA
- Biomedical Informatics and Medical Statistics Department, Medical Research InstituteAlexandria UniversityAlexandriaEgypt
- Clinical Research Department, El‐Gomhoria General HospitalMinistry of health and populationAlexandriaEgypt
| | - Youmna E. Zain
- Medical Research Group of EgyptNegida AcademyArlingtonMassachusettsUSA
- Faculty of MedicineTanta UniversityTantaEgypt
| | - Yasmin Negida
- Medical Research Group of EgyptNegida AcademyArlingtonMassachusettsUSA
- Faculty of MedicineZagazig UniversityZagazigEgypt
| | - Shirin Cadri
- Medical Research Group of RomaniaNegida AcademyArlingtonMassachusettsUSA
- Grigore T. Popa University of Medicine and PharmacyIasiRomania
| | - Nivin Cadri
- Medical Research Group of RomaniaNegida AcademyArlingtonMassachusettsUSA
- Grigore T. Popa University of Medicine and PharmacyIasiRomania
| | - Leslie J. Cloud
- Parkinson's and Movement Disorder CenterVirginia Commonwealth UniversityRichmondVirginiaUSA
| | - Matthew J. Barrett
- Parkinson's and Movement Disorder CenterVirginia Commonwealth UniversityRichmondVirginiaUSA
| | - Brian Berman
- Parkinson's and Movement Disorder CenterVirginia Commonwealth UniversityRichmondVirginiaUSA
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Valls M, Ingvarsson P, Johnels B, Steg G, Thorselius M, Svanborg A. Age-related slowing and fragmentation of a complex movement quantified by optoelectronic kinesiology. Clin Rehabil 2016. [DOI: 10.1177/026921559000400204] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Computer-assisted optoelectronic movement analysis has opened a new field in quantitative laboratory studies of motor function in freely moving humans. In order to establish a method for objective and quantitative documentation of age-related change of a complex movement, a lifting task composed of rising, gait and arm movements was designed. The motor performance of 44 healthy subjects in three age groups was recorded optoelectronically. The change in motor function in the age interval of 40-75 years was mainly due to slower motor performance. In a majority of the subjects aged 85, a movement fragmentation also occurred, indicating deficient co-ordination of rising, gait and arm movements in this age group. The method was found to be well suited to clinical studies of movement pattern and disturbances in elderly subjects. The design of specific tests measuring different aspects of the age-related change in motor function may be of value for sociomedical planning of care and prevention.
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Iwaki H, Nishikawa N, Nagai M, Tsujii T, Yabe H, Kubo M, Ieiri I, Nomoto M. Pharmacokinetics of levodopa/benserazide versus levodopa/carbidopa in healthy subjects and patients with Parkinson's disease. ACTA ACUST UNITED AC 2014. [DOI: 10.1111/ncn3.152] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hirotaka Iwaki
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Noriko Nishikawa
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Masahiro Nagai
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Tomoaki Tsujii
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Hayato Yabe
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Madoka Kubo
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
| | - Ichiro Ieiri
- Department of Clinical Pharmacokinetics; Graduate School of Pharmaceutical Science, Kyushu University; Maidashi Higashiku Fukuoka Japan
| | - Masahiro Nomoto
- Department of Neurology and Clinical Pharmacology; Ehime University Graduate School of Medicine; Tohon Ehime Japan
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Ai C, Wang Y, Li Y, Li Y, Yang L. A 3-D QSAR Study of Catechol-O-Methyltransferase Inhibitors Using CoMFA and CoMSIA. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/qsar.200730053] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Learmonth DA, Bonifácio MJ, Soares-da-Silva P. Synthesis and Biological Evaluation of a Novel Series of “Ortho-Nitrated” Inhibitors of Catechol-O-methyltransferase. J Med Chem 2005; 48:8070-8. [PMID: 16335931 DOI: 10.1021/jm0580454] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Novel regioisomeric "ortho-nitrated" catechols related to the catechol-O-methyltransferase (COMT) inhibitors BIA 3-202 3 and BIA 3-335 4 were synthesized and biologically evaluated. Changing the position of the nitro group from the "classical" meta- to the ortho-position relative to the side-chain substituent of the nitrocatechol pharmacophore exerted profound effects on selectivity and duration of COMT inhibition. Alkylaryl compounds 7a-d possessed shorter duration of action than their regioisomers, but 7b displayed reversed selectivity over 3 at 3 and 6 h, exhibiting preferential central inhibition. In the amino-substituted series, ortho-nitrated regioisomer 14k was less peripherally selective than 4 and short-acting, whereas decahydroquinoline 14g displayed an unprecedented combination of long-acting and selective peripheral inhibition. 7b could provide a useful tool to probe the pharmacological utility of short-acting, centrally selective COMT inhibitors in the treatment of depression in Parkinsonian patients, and 14g represents a promising candidate for clinical evaluation as an adjunct to L-Dopa therapy.
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Affiliation(s)
- David A Learmonth
- Laboratory of Chemistry, Department of Research & Development, BIAL, 4745-457 S. Mamede do Coronado, Portugal
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6
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Abstract
The Movement Disorder Society Task Force for Rating Scales for Parkinson's Disease prepared a critique of the Unified Parkinson's Disease Rating Scale (UPDRS). Strengths of the UPDRS include its wide utilization, its application across the clinical spectrum of PD, its nearly comprehensive coverage of motor symptoms, and its clinimetric properties, including reliability and validity. Weaknesses include several ambiguities in the written text, inadequate instructions for raters, some metric flaws, and the absence of screening questions on several important non-motor aspects of PD. The Task Force recommends that the MDS sponsor the development of a new version of the UPDRS and encourage efforts to establish its clinimetric properties, especially addressing the need to define a Minimal Clinically Relevant Difference and a Minimal Clinically Relevant Incremental Difference, as well as testing its correlation with the current UPDRS. If developed, the new scale should be culturally unbiased and be tested in different racial, gender, and age-groups. Future goals should include the definition of UPDRS scores with confidence intervals that correlate with clinically pertinent designations, "minimal," "mild," "moderate," and "severe" PD. Whereas the presence of non-motor components of PD can be identified with screening questions, a new version of the UPDRS should include an official appendix that includes other, more detailed, and optionally used scales to determine severity of these impairments.
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Learmonth DA, Vieira-Coelho MA, Benes J, Alves PC, Borges N, Freitas AP, da-Silva PS. Synthesis of 1-(3,4-dihydroxy-5-nitrophenyl)-2-phenyl-ethanone and derivatives as potent and long-acting peripheral inhibitors of catechol-O-methyltransferase. J Med Chem 2002; 45:685-95. [PMID: 11806720 DOI: 10.1021/jm0109964] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A homologous series of novel nitro-catechol structures (7a-7e) were synthesized and tested as inhibitors of the enzyme catechol-O-methyltransferase (COMT). Increasing chain length was found to have significant impact on both brain penetration and duration of COMT inhibition in the rat. Of this series, compound 7b (1-(3,4-dihydroxy-5-nitrophenyl)-2-phenyl-ethanone) was found to exhibit the most potent and selective inhibition of peripheral COMT, with an inhibition profile more similar to entacapone 2 than tolcapone 1 (an equipotent peripheral and central inhibitor) but with much improved duration of action (7b, 70% inhibition and 2, 25% inhibition at 9 h after administration). The effects of structural modifications to 7b on COMT inhibitory profile were investigated, and it is concluded that the carbonyl group and preferably unsubstituted aromatic ring are essential features to maintain prolonged peripheral COMT inhibition. The introduction of the alpha-methylene group, the major structural difference between 7b and 1, would appear responsible for the observed enhancement in selectivity of peripheral COMT inhibition of 7b, which has more limited access to the brain than 1.
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Affiliation(s)
- David A Learmonth
- Department of Research & Development, BIAL, 4745-457 S. Mamede do Coronado, Portugal
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Rascol O, Brooks DJ, Korczyn AD, De Deyn PP, Clarke CE, Lang AE. A five-year study of the incidence of dyskinesia in patients with early Parkinson's disease who were treated with ropinirole or levodopa. N Engl J Med 2000; 342:1484-91. [PMID: 10816186 DOI: 10.1056/nejm200005183422004] [Citation(s) in RCA: 1114] [Impact Index Per Article: 46.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND There is debate about whether the initial treatment for patients with Parkinson's disease should be levodopa or a dopamine agonist. METHODS In this prospective, randomized, double-blind study, we compared the safety and efficacy of the dopamine D2-receptor agonist ropinirole with that of levodopa over a period of five years in 268 patients with early Parkinson's disease. If symptoms were not adequately controlled by the assigned study medication, patients could receive supplementary levodopa, administered in an open-label fashion. The primary outcome measure was the occurrence of dyskinesia. RESULTS Eighty-five of the 179 patients in the ropinirole group (47 percent) and 45 of the 89 patients in the levodopa group (51 percent) completed all five years of the study. In the ropinirole group 29 of the 85 patients (34 percent) received no levodopa supplementation. The analysis of the time to dyskinesia showed a significant difference in favor of ropinirole (hazard ratio for remaining free of dyskinesia, 2.82; 95 percent confidence interval, 1.78 to 4.44; P<0.001). At five years, the cumulative incidence of dyskinesia (excluding the three patients who had dyskinesia at base line), regardless of levodopa supplementation, was 20 percent (36 of 177 patients) in the ropinirole group and 45 percent (40 of 88 patients) in the levodopa group. There was no significant difference between the two groups in the mean change in scores for activities of daily living among those who completed the study. Adverse events led to the early withdrawal from the study of 48 of 179 patients in the ropinirole group (27 percent) and 29 of 89 patients in the levodopa group (33 percent). The mean (+/-SD) daily doses given by the end of the study were 16.5+/-6.6 mg of ropinirole (plus 427+/-221 mg of levodopa in patients who received supplementation) and 753+/-398 mg of levodopa (including supplements). CONCLUSIONS Early Parkinson's disease can be managed successfully for up to five years with a reduced risk of dyskinesia by initiating treatment with ropinirole alone and supplementing it with levodopa if necessary.
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Affiliation(s)
- O Rascol
- Clinical Investigation Center, Neuropharmacology Unit, INSERM Unité 455, University Hospital, Toulouse, France.
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Bonifati V, Meco G. New, selective catechol-O-methyltransferase inhibitors as therapeutic agents in Parkinson's disease. Pharmacol Ther 1999; 81:1-36. [PMID: 10051176 DOI: 10.1016/s0163-7258(98)00032-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Levodopa remains the most effective drug for Parkinson's disease (PD). However, its benefits are limited owing to extensive metabolism by catechol-O-methyltransferase (COMT), especially if levodopa is used in combination with peripheral dopa-decarboxylase inhibitors. A new generation of potent, orally active, selective, and reversible COMT inhibitors has become available recently. Among these, tolcapone and entacapone have been best characterised. Preclinical and clinical studies have shown that COMT inhibitors markedly enhance levodopa availability and prolong its plasma half-life. In recent large clinical trials they proved to be able to ameliorate motor fluctuations, reduce disability, and decrease levodopa requirements in PD patients. The tolerability profiles of entacapone and tolcapone are good. COMT inhibition promises to become an important means of extending the benefits of levodopa therapy in PD.
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Affiliation(s)
- V Bonifati
- Department of Neurosciences, University La Sapienza, Rome, Italy
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10
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Neau SH, Chow MY, Chafetz L. The influence of reaction conditions on the derivatization of carbidopa by β-dicarbonyl compounds for enhanced optical rotation. Int J Pharm 1994. [DOI: 10.1016/0378-5173(94)90319-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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11
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Boomsma F, Meerwaldt JD, Man in't Veld AJ, Hovestadt A, Schalekamp MA. Treatment of idiopathic parkinsonism with L-dopa in the absence and presence of decarboxylase inhibitors: effects on plasma levels of L-dopa, dopa decarboxylase, catecholamines and 3-O-methyl-dopa. J Neurol 1989; 236:223-30. [PMID: 2760634 DOI: 10.1007/bf00314504] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The effect of levodopa (L-dopa), alone or in combination with a peripheral decarboxylase inhibitor (PDI), on plasma levels of aromatic-L-amino acid decarboxylase (ALAAD, = dopa decarboxylase), L-dopa, 3-O-methyl-dopa (3-OMD), dopamine (DA), noradrenaline, adrenaline and dopamine beta-hydroxylase has been studied. In healthy subjects and in patients with parkinsonism plasma ALAAD level fell after administration of L-dopa + benserazide, but returned to previous levels within 90 min. In a cross-sectional study blood was obtained, 2 h after dosing, from 104 patients with idiopathic parkinsonism, divided into four groups: no L-dopa treatment (group 1), L-dopa alone (group 2), L-dopa + benserazide (Madopar) (group 3) and L-dopa + carbidopa (Sinemet) (group 4). Plasma ALAAD, which was normal in groups 1 and 2, was increased 3-fold in groups 3 and 4, indicating that there was induction of ALAAD by the co-administration of PDI. Despite this induction of ALAAD, in groups 3 and 4, with half the daily L-dopa dose compared with group 2, plasma L-dopa and 3-OMD levels were 5 times higher, while plasma DA levels were not different. The DA/L-dopa ratio was decreased 5-fold in group 2 and 16-fold in groups 3 and 4 as compared with group 1. Neither 3-OMD levels nor 3-OMD/L-dopa ratios correlated with the occurrence of on-off fluctuations. In a longitudinal study of three patients started on Madopar treatment the induction of plasma ALAAD was found to occur gradually over 3-4 weeks. Further detailed pharmacokinetic studies in plasma and cerebrospinal fluid are required in order to elucidate whether the ALAAD induction by PDI may be related to the loss of clinical efficacy of combination therapy in some patients and how it is related to end-of-dose deterioration and on-off phenomena.
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Affiliation(s)
- F Boomsma
- Department of Internal Medicine I, University Hospital Dijkzigt, Erasmus University, Rotterdam, The Netherlands
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12
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Abstract
Of the neurological disorders, none can claim a battery of therapeutic agents based upon as rational a pharmacology as can Parkinson's disease. In this review, the clinical pharmacokinetics of the major classes of anti-Parkinsonian drugs is discussed. Although they are the oldest drugs in the anti-Parkinsonian armamentarium, little pharmacokinetic data are available regarding the anticholinergic and antihistaminic agents. Based on elimination half-lives of 10 to 18 hours, most could probably be effectively given on a twice-daily schedule. Amantadine is unique among anti-Parkinsonian agents both in lacking a clearly defined mechanism of action and in being eliminated from the body exclusively by renal excretion of unchanged drug. Thus the normal decline of renal function in the elderly Parkinsonian population becomes an important factor in avoiding potential drug toxicity. The pharmacokinetics and pharmacodynamics of levodopa are complex. Since it is an amino acid, it follows metabolic pathways and must compete for absorption and brain uptake with a number of large neutral amino acids. It has a short elimination half-life and, as Parkinson's disease progresses, the brain loses its capacity to store the drug and becomes dependent in a moment-to-moment fashion on plasma levodopa concentrations, creating therapeutic response fluctuations in over 50% of patients. Pharmacokinetic considerations in the management of these response fluctuations are discussed. The newest class of anti-Parkinsonian agents are the direct acting dopamine receptor agonists. These drugs, all derivatives of ergot, have more prolonged durations of anti-Parkinsonian action than levodopa. However, other than bromocriptine, clinical experience with members of this class of drugs is still limited.
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Affiliation(s)
- J M Cedarbaum
- Cornell University Medical College, Burke Rehabilitation Center, White Plains, New York
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Bermejo Pareja F, Martinez-Martin P, Muradas V, de Yébenes JG. Carbidopa dosage modifies L-dopa induced side effects and blood levels of L-dopa and other amino acids in advanced parkinsonism. Acta Neurol Scand 1985; 72:506-11. [PMID: 4082917 DOI: 10.1111/j.1600-0404.1985.tb00908.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Thirty-four patients with advanced Parkinson's disease showing intolerance to therapeutic doses of L-DOPA were treated with L-DOPA plus carbidopa at two different proportions. Ten patients preferred medication containing 10% carbidopa while 24 preferred 25% carbidopa. The increase of carbidopa reduced gastrointestinal disturbances and psychiatric side effects related to L-DOPA, but improvement of disability when measured according to objective tests was modest. Higher doses of carbidopa reduced peripheral DOPA metabolism and increased blood levels of tryptophan, 3-OM-DOPA and DOPA in relation to the administered dose.
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Kaakkola S, Männistö PT, Nissinen E, Vuorela A, Mäntylä R. The effect of an increased ratio of carbidopa to levodopa on the pharmacokinetics of levodopa. Acta Neurol Scand 1985; 72:385-91. [PMID: 4082903 DOI: 10.1111/j.1600-0404.1985.tb00888.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A randomized, cross-over study was designed to compare the effects of an increased ratio (from 1:10 to 1:4) of carbidopa to levodopa on the fate of levodopa and carbidopa in 11 healthy subjects. Four combinations of carbidopa/levodopa (10 mg/100 mg, 25 mg/100 mg, 25 mg/250 mg, 62.5/250 mg) were used. Plasma levodopa, carbidopa, dopamine and dopac concentrations as well as urinary excretions of levodopa and dopac were determined by a sensitive high-performance liquid chromatography with electrochemical detection after a single carbidopa/levodopa tablet. As the ratio of carbidopa to levodopa increased, there was a significant increase in apparent t1/2 and AUC values of levodopa. At the same time the urinary excretion of levodopa increased and that of dopac decreased. The plasma ratios of levodopa/dopamine and levodopa/dopac and the urinary ratio of levodopa/dopac also increased. There were less subjective side-effects in the 1:4 groups than in the 1:10 groups. It is concluded that increasing the amount of carbidopa in relation to levodopa may be beneficial and further clinical studies are clearly indicated.
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Rauws AG, Vos JG, Garbis-Berkvens JM, Peters PW, de Vries T, van Logten MJ. Comparative 90-day toxicity of two decarboxylase inhibitors, benserazide and carbidopa, in the rat. Toxicol Appl Pharmacol 1982; 66:201-20. [PMID: 7164099 DOI: 10.1016/0041-008x(82)90285-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
It is useful to divide Parkinsonian patients into those whose signs are confined to tremor, rigidity and akinesia, and those with evidence of a more diffuse disturbance. The treatment of choice in the former is levodopa combined with a peripheral decarboxylase inhibitor. At the onset of the disease, when disability is minimal, amantadine or anticholinergic drugs may suffice. Bromocriptine is useful in some patients who derive only short-lived benefit from each dose of levodopa. The role of stereotactic surgery is now confined to patients with an incapacitating unilateral tremor which has not improved with drug therapy. In elderly patients with evidence of diffuse cerebral dysfunction such as dementia, grasp reflex, hyper-reflexia or severe postural hypotension, the beneficial effect of these drugs is often outweighed by the side effects. Small doses of levodopa alone may be tried. Anticholinergic drugs and amantadine should be avoided in such patients.
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