Reduced L-dopa absorption and increased clinical fluctuations in Helicobacter pylori-infected Parkinson's disease patients

We report that the area under the curve of L-dopa plasma concentration, fol lowing the administration of a single 250 mg L-dopa dose, is augmented afte r Helicobacter pylori (HP) eradication in six Parkinson's disease (PD) pati ents showing high IgG antibody titer against HP. A prolongation of L-dopa c linical benefit was also observed. We suggest that HP infection-activated g astric alterations may be responsible, at least in pare, for the reported e rratic efficacy of oral L-dopa therapy in some advanced PD patients. Given the high percentage of HP-positivity in the age cohorts including the large st prevalence of PD patients, we propose that HP eradication be recommended in all PD patients under L-dopa therapy.