- Use of concomitant therapy likely to affect cognition, Medication prohibited 28 days prior to randomisation: benzodiazepines, amphetamines, reboxitin, atomoxinetine, buspiron, donepezil, duloxetine, galantamine, ginko biloba, memantine, methylphenidate, modafinil, rivastigmine, tacrine, smoking cessation therapy varencicline and any dosage form of nicotine replacement therapy. Medication prohibited 14 days prior to randomisation: irreversible monoamine oxidase inhibitors (MAOI), tricyclic antidepressants (TCA), biperiden, antoicholinergic agents (even if the indications are extra pyramidal symptoms or urinary symptoms)