Background Validation of antineoplastic prescriptions is an important job in hospital pharmacy to ensure appropriate patient treatment.

Purpose To evaluate the prescribing errors in antineoplastic orders detected during oncology pharmacist validation.

Materials and Methods We conducted a two year prospective study (2010–2011) in which all prescriptions containing antineoplastic agents were reviewed for errors and all were accounted for in the analysis. Adjuvant medicines were excluded. One oncology pharmacist and one second year pharmacy resident were needed for this work. Prescriptions included: standardised chemotherapy order forms (SCOFs), individually typed and handwritten prescriptions. The primary outcome was the number of prescribing errors detected. The error rate was calculated by the ratio of the total number of prescription errors to the volume of prescriptions. Prescribing errors were then classified as follows: dose changed, antineoplastic error, dose reduction error, dose calculation error, dose omission, scheme changed, acronym changed, wrong patient identification, failure of therapeutic programme, antineoplastic omission and addition.

Results The number of prescribing errors detected was 80. The error rate was 0.55% (for a total of 14,600 prescriptions). Principal types of errors detected were: dose changed (1%), antineoplastic error (5%), dose reduction error (14%), dose calculation error (32%), dose omission (12%), scheme changed (12%), acronym changed (1%), wrong patient identification (1%), failure of therapeutic programme (16%), antineoplastic omission (5%) and addition (1%). None of the errors reached the patient.

Conclusions Our study points to the fact that, although chemotherapy prescribing errors are intercepted during pharmacist validation and do not reach the patient, there are still some problems in the chemotherapy ordering process and we should target preventive measures in order to improve patient safety.

No conflict of interest.