Background and importance Drugs used for COVID-19 (lopinavir/ritonavir, hydroxychloroquine) have a large number of interactions. If any of these drugs are used, we should be cautious and monitor the clinical evolution of each patient closely. The hospital pharmacist plays an important role in the revision of treatment to ensure its safety and efficacy.

Aim and objectives To analyse potential drug interactions of treatment for COVID-19 and to evaluate physician acceptance of pharmacist recommendations.

Material and methods This was a prospective interventional study from March to May 2020. We included all patients who started antiviral treatment for COVID-19 with a positive PCR test and hospital admission. Data were collected from the electronic medical record (DIRAYA) and the prescription programme (PRISMA). The databases used for the detection of interactions were: Drugs.com and COVID-19 drug interactions.org (University of Liverpool).

Collected data were age, sex, concomitant medication, interaction classified according to severity (major/moderate), mechanism of the interaction (MI) (pharmacokinetic/pharmacodynamic), drugs that prolong QT interval and pharmaceutical recommendation (PR).

Detection of an interaction was reported in the clinical course of the patient. In the case of a serious interaction or clinical risk situation, the prescribing doctor was notified directly. Descriptive statistics were used to analyse the results.

Results 178 patients (56.2% men) were analysed, with a median age of 63 (range 22–90) years. 267 interactions were detected (56.9% moderate/43.1% major). The MI involved was pharmacokinetic (63.9%)/pharmacodynamic (36.1%). 22.8% of the collected drugs could affect the QT interval.

Antiviral therapy used was lopinavir/ritonavir (96.6%) and hydroxychloroquine (94.9%). 72.5% of patients had at least one interaction. The main therapeutic groups involved were: 15.7% selective calcium channel blockers, 11.2% topical nasal corticosteroids, 10.5% angiotensin II receptor blockers and 8.8% HMG-COA reductase inhibitors. 185 PR were made. The rate of acceptance was 70.8%: 35.2% change dose, 24.1% change treatment and 11.5% drug suspension.

Conclusion and relevance Pharmacist participation in the multidisciplinary COVID team was relevant for the detection of multiple interactions, helping doctors in decision making about drugs not commonly used in an overwhelmed healthcare situation.

References and/or acknowledgements

1. https://www.drugs.com/

2. https://www.druginteractions.org/

Conflict of interest No conflict of interest