Background At least 50% of patients admitted to hospital for surgery take medicines to treat chronic diseases. Some medicines may interact with drugs used during surgery, but there are few situations that contraindicate this use. Most drugs must be maintained in the perioperative period, administering the last dose 2 h before surgery and restoring with oral intake. Others must be stopped, replaced or temporarily administered by another route. Heightened awareness and diligent documentation of patient medications from admission to discharge can reduce serious problems in the perioperative period.

Purpose To implement an evidence based protocol for managing chronic medication in the perioperative period.

Material and methods An anaesthesiologist, orthopaedic surgeon and two hospital pharmacists formed the multidisciplinary team. A Pubmed search was performed using the following terms: perioperative, chronic, medication and management. Studies were reviewed and a protocol with management recommendations before surgery, surgery day and after surgery was made. A guide in book form was developed and distributed by the surgical services.

Results 13 articles and some evidence based guidelines with strength therapeutic recommendations were reviewed. Drugs reviewed were grouped into 9 blocks as the system on which they act, and on this basis, management recommendations were established. A section of herbal medicines with specific recommendations for those for which there is increasing evidence were included. 58 therapeutic groups were reviewed according to ATC classification level 3. Of these, 53.4% ​​were recommended to continue treatment, 8.6% to assess according to clinical status and 38% to discontinue. It was generally recommended to discontinue therapy with: cyclooxygenase-1, -2 inhibitors, cyclophosphamide, immunosuppressives, biologics, antihyperuricaemic drugs, potassium supplements, diuretics, fibrates, haemorheologics, new oral anticoagulants, hormone replacement therapy, oestrogen modulators, bisphosphonates, systemic hormonal contraceptives, oral hypoglycaemic agents, monoamine oxidase inhibitors, lithium, phosphodiesterase inhibitors, vitamins and nutritional supplements. Herbal medicines are recommended to discontinue 7–10 days before surgery.

Conclusion Epidemiological studies on the management of perioperative drugs are heterogeneous. It is recommended to continue treatment with most drugs but information does not come from clinical trials, but expert opinion, case reports or theoretical considerations. While for some drugs there are good consensus recommendations, for others the available information is limited or controversial; which leads to the coexistence of several trends in clinical practice.

No conflict of interest.