Preventable medication errors occur at all stages of the medicines use process. Prescribing is no exception to this.

Prescription is the first stage in the medicines use process and prescribing errors are possibly the most serious of all types of medication errors. Unless a prescribing error is detected by another person involved in medicine use, such as the pharmacist dispensing the medicine, the nurse administering the medicine or the patient for whom the medicine was prescribed, incorrect medicines will be taken or given, with the risk of harm. The extent to which a prescribing error causes harm will depend on the drug prescribed, the magnitude of the error if it is a dosing error, the number of doses of the incorrect prescription the patient receives, the clinical status of the patient exposed to the error and the setting in which the error occurs. The same error in two different patients can have very different outcomes.

Traditionally only doctors and dentists could prescribe medicines. Now pharmacists, nurses and allied health professionals are extending their patient care roles and prescribing either as supplementary prescribers in partnership with independent prescribers or independently in their own right. These new prescribers will be vulnerable to the same systemic causes of prescribing error as traditional prescribers.

This chapter describes prescribing errors, their causes and actions to be taken to minimise the risk of prescribing error.