Table 1 Search strategy for each database

PubMed

#1: (((((COVID-19[MeSH Terms]) OR ("SARS-CoV-2 Infection")) OR ("2019 Novel Coronavirus Infection")) OR ("2019 nCoV Disease")) OR ("Coronavirus Disease 2019")) OR (Coronavirus)

#2: Polypharmacy [MeSH Terms]

#3: (((Polypharmacy) OR (poly medication)) OR ("multiple drugs")) OR ("Potentially inappropriate medications")

#4: (((((Outcome) OR (Mortality)) OR (death)) OR (morbidity)) OR (complication)) OR ("drug interactions")

#5: #1 AND (#2 OR #3) AND #4

143

Web of science

#1: ALL = (Polypharmacy OR polymedication OR "multiple drug" OR "Potentially inappropriate medications")

#2: ALL = (Outcome OR Mortality OR death OR morbidity OR complication OR "drug interactions")

#3: TS = ("COVID-19" OR "SARS-CoV-2 Infection" OR "2019 Novel Coronavirus Infection" OR "2019 nCoV Disease" OR "Coronavirus Disease 2019" OR Coronavirus)

#4: #1 AND #2 AND #3

68

Scopus

#1: TITLE-ABS-KEY ("COVID-19" OR "SARS-CoV-2 Infection" OR "2019 Novel Coronavirus Infection" OR "2019 nCoV Disease" OR "Coronavirus Disease 2019" OR coronavirus)

#2: ALL (outcome OR mortality OR death OR morbidity OR complication OR "drug interactions")

#3: TITLE-ABS-KEY ((polypharmacy OR polymedication OR "multiple drug" OR "Potentially inappropriate medications")

#4: #1 AND #2 AND #3

252

Embase

#1: ‘covid 19’:ti,ab,kw OR ‘sars-cov-2 infection’:ti,ab,kw OR ‘2019 novel coronavirus infection’:ti,ab,kw OR ‘2019 ncov disease’:ab,kw OR 'coronavirus disease 2019':ti,ab,kw OR coronavirus:ti,ab,kw

#2: polypharmacy:de

#3: polypharmacy:ti,ab,kw OR polymedication:ti,ab,kw OR 'multiple drug':ti,ab,kw OR 'potentially inappropriate medications':ti,ab,kw

#4: outcomes:ti,ab,kw OR mortality:ti,ab,kw OR death:ti,ab,kw OR morbidity:ti,ab,kw OR complication:ti,ab,kw OR 'drug interactions':ti,ab,kw

#5: #2 OR #3

#6: #1 AND #4 AND #5

138

ScienceDirect

Title, abstract or author-specified keywords (COVID-19 OR "sars-cov-2") AND (Polypharmacy OR polymedication OR "multiple drug" OR "Potentially inappropriate medications")

38

ProQuest

#1: (Polypharmacy OR polymedication OR "multiple drug" OR "Potentially inappropriate medications")

#2: (Outcome OR Mortality OR death OR morbidity OR complication OR "drug interactions")

#3: TI,AB("COVID-19" OR "SARS-CoV-2 Infection" OR "2019 Novel Coronavirus Infection" OR "2019 nCoV Disease" OR "Coronavirus Disease 2019" OR Coronavirus)

#4: #1 AND #2 AND #3

389