Background Patients' own medicines (POMs) are medicines that patients have obtained in the community setting and bring to the hospital when admitted. Literature suggests that using POMs has benefits to the patient and the hospital that include improving the accuracy of admission prescriptions and continuity of care as well as reducing medicine costs. Nonetheless the quality and the practice of using POMs have been poorly investigated.

Purpose To evaluate the quantity and quality of POMs to assess the disadvantages and benefits of using them.

Materials and methods Clinical pharmacists in 4 wards comprised of 3 acute care wards and 1 geriatric ward at 3 different hospitals in Denmark evaluated POMs for quantity and quality. The POMs were evaluated on their appearance, container, labelling, identification, storage conditions and expiry date. POMs were defined suitable for use if the medicine was intact, labelled with patient ID, in original container, had visibly not exceeded the expiry date, appeared clean and the contents could be verified. Current policies in Zealand Region allow POMs to be used if they meet the above criteria and if no suitable substitute (generic or equivalent) is stocked in the hospital.

Results During March 2010 to July 2011 529 patients were assessed by the clinical pharmacist. According to medicines histories the patients took 4600 medicines (including over the counter medicines and supplements) averaging 8.7 per patient. A total of 60% patients (315) brought POMs, equivalent to 44% (2035) of the medicines from the medicine history to the hospital. The majority of the POMs were suitable for use according to the criteria set, although only a small percentage were actually used under the criteria that no suitable substitute was available.

Conclusions More than half of patients bring their own medicine to the hospital and the majority of POMs are suitable for use. Only a small proportion are actually used since substitution is often possible.