The frequent association between coronavirus disease 2019 (COVID-19) and olfactory dysfunction is creating an unprecedented demand for a treatment of the olfactory loss. Systemic corticosteroids have been considered as a therapeutic option. However, based on current literature, we call for caution using these treatments in early COVID-19-related olfactory dysfunction because: (1) evidence supporting their usefulness is weak; (2) the rate of spontaneous recovery of COVID-19-related olfactory dysfunction is high; and (3) corticosteroids have well-known potential adverse effects. We encourage randomized placebo-controlled trials investigating the efficacy of systemic steroids in this indication and strongly emphasize to initially consider smell training, which is supported by a robust evidence base and has no known side effects.

2nd Academic ORL Department Papageorgiou Hospital Aristotle University Thessaloniki Greece

Department of Anatomy Université du Québec à Trois Rivières Trois Rivières Quebec Canada

Department of Otolaryngology Head and Neck Surgery University of Colorado Anschutz Medical Campus Aurora Colorado

Department of Otorhinolaryngology and Head and Neck Surgery Hospital of Pardubice Pardubice Czech Republic

Department of Otorhinolaryngology Biruni University Istanbul Turkey

Department of Otorhinolaryngology Cliniques universitaires Saint Luc Brussels Belgium

Department of Otorhinolaryngology Head and Neck Surgery Rhinology Olfactory Unit Geneva University Hospitals Geneva Switzerland

Department of Otorhinolaryngology Head and Neck Surgery University Hospital Basel CH 4051 Basel Switzerland

Department of Otorhinolaryngology Inselspital University Hospital Bern Bern Switzerland

Department of Otorhinolaryngology Medical University of Vienna Vienna Austria

Department of Rhinology Royal National ENT Hospital University College London Hospitals NHS Foundation Trust London UK

ENT clinic Asst Settelaghi University of Insubriae Varese Italy

Flavour Clinic Department of Otorhinolaryngology Regional Hospital West Jutland Holstebro Denmark

Flavour Institute Aarhus University Aarhus Denmark

Institute of Neuroscience Univeristé catholique de Louvain Brussels Belgium

Massachusetts Eye and Ear Harvard University Boston Massachusetts

Norwich Medical School University of East Anglia Norwich UK

Section of Otolaryngology Head and Neck Surgery The University of Chicago Chicago Illinois

Smell and Taste Clinic Department of Otorhinolaryngology TU Dresden Dresden Germany

The Centre for Olfactory Research and Applications Institute of Philosophy School of Advanced Study London UK

The Norfolk Smell and Taste Clinic Norfolk and Waveney ENT Service Gorleston UK

UCL Ear Institute University College London London UK

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