Timing of levodopa therapy.

Abstract

The introduction of levodopa in the treatment of parkinsonism 1,2 marked a milestone in changing the perceptions of neurology as academically rich but therapeutically sterile. A classic degenerative disorder became a treatable neurotransmitter deficiency. Discoveries in medicine tend to follow the outline of an electrocardiogram, with the P representing initial interest, Q the initial doubt, R the bandwagon, S the backlash, and T the final truth. 3 With levodopa therapy we are somewhere between the S and the T. Dr Melamed marshalls the results of a large number of clinical and experimental studies to support his view that levodopa administration eventually limits its own usefulness. Hence, levodopa treatment should be delayed as long as possible. Drs Markham and Diamond argue from their results in three groups of parkinsonian patients that the slope of deterioration is the same regardless of the time of initiation of therapy. Hence, levodopa treatment should not