Tacrine Levodopa

Tacrine may reduce the efficacy of levodopa in Parkinson s disease... 

The Cochrane Library is a relatively new and growing electronic library that provides more than 850 summaries of published literature about pharmaceutical and other interventions to improve health. The Library adds new titles four times a year to its cumulative online and CD versions (the latter, available by subscription, offers more databases). The Library s 2000 Issue 3 contains evidence on dozens of clinical dilemmas, such as antibiotic treatment for traveler s diarrhea, antileukotriene agents compared to inhaled corticosteroids in the management of recurrent and/or chronic asthma, opioid antagonists for alcohol dependence, and bromocriptine versus levodopa in early Parkinson s disease. The Cochrane Library also updates earlier reviews when important new evidence becomes available. Among the newest updates are tacrine for Alzheimer s disease, tricyclic and related drugs for nocturnal enuresis in children, and nicotine replacement therapy for smoking cessation. 

The mild parkinsonism of an elderly woman with Alzheimer s disease worsened, leading to severe tremor, stiffness and gait dysfunction within 2 weeks of doubling her tacrine dosage from 10 mg to 20 mg four times daily. This improved when levodopa/carbidopa was started, but the tremor returned when tacrine was increased to 30 mg four times daily. The symptoms disappeared when the tacrine dosage was reduced to 20 mg four times daily. ... 

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