ABSTRACT
The aim of the study was to assess the pharmacokinetic properties and clinical effectiveness of L-dopa/carbidopa solution treatment in patients with parkinsonian motor fluctuations. No significant difference in maximal L-dopa concentration, time to peak L-dopa concentration and area under curve was found in single dose studies which compared equivalent tablet and solution L-dopa/carbidopa doses in 9 patients. Seven out of 10 patients treated with hourly doses of liquid L-dopa/carbidopa were improved after switching from conventional tablet medication. Less 'off' time per day and less 'off' phase disability were the usual benefits. Six of these patients maintained this improvement and continued on long-term liquid medication. The benefits of this treatment do not relate to improved L-dopa delivery to the bloodstream. The ability of patients to fractionate the treatment into small, frequent doses which can be used more flexibly than tablets appears to confer the main advantages of liquid L-dopa/carbidopa in the management of parkinsonian motor fluctuations.
ABSTRACT
Twenty patients with Parkinson's disease were studied during the early phase of L-dopa treatment to clarify the development and progression of Parkinsonian motor fluctuations. Two patients had developed symptomatic motor fluctuations of moderate severity and another 3 had mild fluctuations. Both the initial response to L-dopa and the amplitude of response to a L-dopa test dose after a mean follow up period of 30 months were significantly greater for the fluctuating patients compared with those without fluctuation (p < 0.05). Although severe motor fluctuations do not usually develop until a number of years of L-dopa treatment have elapsed, this study shows that motor fluctuations can be detected quite early in the disease course and tend to appear in those patients who respond best to L-dopa.