Introduction: Potentially reversible dementias are rarely detected in ambulatory care facilities. Actual reversibility is virtually not known and has been occasionally reported in the literature. Aim: Our aim was to determine the prevalence of potentially reversible dementias among patients seen at the ambulatory care facility and to estimate their real life reversibility. Subcjets and methods: A retrospective analysis of medical records of 258 outpatients attending the Memory Clinic of Central University Hospital of Lodz in the years 2002-2003. Results: Potentially reversible dementia has been diagnosed in 18 (5 women, mean age 60.9 +/- 4.9) subjects yielding 7% of all the subjects presented. These patients were significantly younger and the severity of their cognitive deficits was milder as compared to the non-reversible cases. Treatment was successful in only 3 cases, what translates into only 1.5% of the diagnosed as demented. Twenty seven cases with cognitive deficit but no dementia (depression or drugs side-effects) were claimed as potentially reversible and treated, in most cases (22 out of 27), successfully. However, within a 2 year period of follow-up, the development of dementia was observed in 13 of 22 cases. Conclusions: Potentially reversible dementia is a rare phenomenon in ambulatory care facility. The majority of potentially reversible cases can be found among younger and less impaired patients. Even in cases treated successfully, the risk of developing dementia within 2 years is very high.