PRN prescriptions enablehealthcare staff to respond quickly to the urgent clinical needs of the user without having to contact the responsible clinician (RC). One problem, established amongst most institutions by NICE regarding the use of PRN, is that most of these institutions struggle to keep an updated or full record on the PRN medications. Thus, the aim of this audit was to check the record keeping of PRN medications, of two adolescent wards in St Andrews Healthcare Hospital, against the established standards.The standards were acquired from the local trust's medicine policy and are based on good clinical practice and principles. Data were collected over a 3-month period covering all the 16 in-patients of two wards in St Andrew's Healthcare Hospital. Medical case records and drug charts were reviewed retrospectively. All PRN prescriptions were reviewed against the standards. The total percentage of compliance with the standards was analyzed using spreadsheet software.The significant results obtained were that 36% of PRN medications were not cancelled even if they had not been used for >1 month and 23% did not have clear indications of use. Majority of the other standards showed full compliance.Some PRN medications were not cancelled even if not used for >1 month, most likely because it is often uncertain when a service user may require the PRN. This could be overcome by having screening tools such as START/STOP to alert the RC after a month. Also, when filling in the PRN medication chart, clear indication for use must be an obligatory section on the system, in addition to increasing awareness among staff about this common error. Finally, regular review by the RC is required through seasonal audits, especially by medical and pharmaceutical staff, which will help monitor errors as well as increase awareness about PRN prescribing practice.