[Medication and memory: interactions among the elderly].

Several different systems govern human memory, and different drugs may act specifically on one or more of them. The central nervous system in the elderly is particularly sensitive to drugs, and an iatrogenic cause must be sought for all recent and/or sudden alterations in memory functions. In the case of recent alterations in memory, all nonessential drugs, especially psychotropic agents; should be withdrawn or reduced. Elderly persons, especially those with dementia, are at risk because of the frequent and substantial effects of drugs on their memory: the benefit-risk ratio must be evaluated regularly and essential treatments maintained.