Elderly patients are at high risk of corona virus disease 2019 (COVID-2019) infection and severe COVID-19 patients are treated in intensive care units (ICU). Drug-drug interaction risk increased to 100% with eight or more medication use. Comorbidities in both elderly and ICU patients leading to polypharmacy and a higher risk for drug-drug interactions. Also, the organ dysfunctions due to COVID-19 may alter the pharmacokinetics of the drugs which may influence the severity of drug interactions. The severity, mechanisms, onset of action and clinical significance of the drug-drug interactions may vary. Detailed information on COVID-19 drug interactions is reported by The Liverpool Drug Interaction Group, however this paper was aimed to provide a quick guidance on these interactions for the clinicians. During the management of COVID-19, possibility of drug-drug interactions should be considered by clinicians to avoid any negative outcomes in the treatment process.