Can an adjuvant treatment or a pharmacologic prevention be common to several diseases? The case of those associated to neuromediator defects

The author has tried to extrapolate on several neurological diseases of the ageing, Knollʹs proposition to treat Parkinsonʹs disease chronically for relapse prevention, by MAO-B. At this occasion, the author makes a critical review of the clinical trial results concerning the new different series of depression treatments, as most authors propose today to use some new ones not only in depression, but in Parkinsonʹs and Alzheimerʹs diseases and in ageing.