Background The reconciliation process detects medicines errors and is a key point in improving patient safety.

Purpose To analyse the incidence, type and seriousness of reconciliation errors at admission to a Cardiology Unit.

Materials and methods Descriptive prospective observational study in September 2013 in patients admitted to the Cardiology Unit in a tertiary hospital. Demographic data: sex and age.

The patient’s usual long-term treatment, obtained by a thorough interview with the patient and by reviewing the clinical history, was compared with medicines prescribed upon admission in order to identify: No Discrepancies (ND), Intentional Discrepancies (ID) (formulary substitutions/modifications in response to patient’s clinical status) and apparently unexplained Discrepancies Requiring Clarification with the physician (DRC). After clarification, Reconciliation Errors (RE) (discrepancies resulting in physician order changes) were classified by type and severity.

Results 75 patients were admitted. Only 25 were reconciled due to logistical reasons. The median age was 74.9 ± 8.9 years. 64% were male.

315 medicines were investigated: 75 ND (23.81%), 193 ID (61.27%) and 47 DRC (14.92%).

After clarification, 37 (78.72%) DRC were RE. 11.75% of prescriptions (37/315) were RE.

RE affected 19 (76%) of the study patients. The average RE per patient was 1.95.

Types of RE were: omissions (n = 25), different dose/route/frequency (n = 3), unnecessary medicines (n = 2), wrong medicine (n = 1) and incomplete prescription (n = 6).

In terms of severity, RE were distributed as follows: No error, but possible (n = 8), errors that did not reach the patient (n = 22), errors that reached the patient but were not harmful (n = 6) and errors that caused temporary harm requiring intervention (n = 1).

Conclusions The process of taking a pharmacotherapeutic history at hospital admission is inadequate since three out of four patients showed RE, mostly omissions.

Although most of RE caused no damage, if perpetuated at discharge, they might have worse consequences and/or affect the effectiveness of treatment.

The pharmacist’s work in hospitalisation units is vital to reduce errors in care transitions and represents an opportunity to draw attention to the medicines in order to increase patient safety.

No conflict of interest.