Background The addition of a pharmacist during the validation, preparation and administration of cytostatics ensures the detection and resolution of drug-related problems.

Purpose To quantify and analyse the pharmacist’s contribution during the validation process, to ensure safety during all the stages of use of cytostatic drugs.

Material and methods A prospective observational study of 4 months. All pharmacist interventions (PIs) related to medication errors (MEs) were recorded, from the prescription to the administration of chemotherapy. All prescriptions associated with chemotherapy, biological treatments and supportive care drugs were considered. The MEs and their severity were classified according to the Updated Classification of Medication Errors, by the Ruiz-Jarabo group 2000. The variables recorded were: potential gravity, if it reached the patient, drugs involved and medical policy.

Results During the study period 38 PIs were recorded (24 drugs involved). PIs were made more often during the prescription process (86.8%), followed by administration (7.9%) and preparation (5.3%). Of these, in 81.6% of cases a cytostatic and/or biological agent was involved, and 18.4% involved a supportive care drug. The severity of PIs was: 18.4% minor, 31.6% moderate, 42.1% severe and 7.9% very severe. They reached the patient in 10.5% of cases. The drugs involved more often were carboplatin (33.3%), aprepitant (20.8%), paclitaxel (16.67%), azacitidine (12.5%), irinotecan, oxaliplatin and vincristine (5.3% each). The main MEs were: omission of medicine needed (26.3%), dose higher than needed (15.8%), omission in transcription (13.2%), dose lower than needed (10.5%), administration error (7.9%) and preparation error (5.3%).

Conclusion The pharmacist’s contribution prevented 89.5% of MEs from reaching the patient. These results reveal the importance of incorporating the pharmacist as an essential part of a multidisciplinary team to contribute to the safety of patients. The pharmacist should have a more active role in the areas of medicines preparation and administration; an appropriate ratio of pharmacists vs. number of validated patients is needed.

References and/or acknowledgements Ruiz-Jarabo 2000.

No conflict of interest.