To understand and manage potential drug-drug interactions in COVID-19 treatments, key pharmacological, biochemical, and physiological concepts are classified into the following groups:

• General Pharmacology: Pharmacokinetics and pharmacodynamics.
• Drug Transporters: Organic Anion Transporters (OAT), Organic Anion Transporting Polypeptides (OATP), Organic Cation Transporters (OCT), and P-glycoprotein (P-gp/MDR1).
• Intracellular Signaling Pathways: Janus Kinases (JAK), Signal Transducers and Activators of Transcription (STAT), and Mechanistic Target of Rapamycin (mTOR).
• Enzymatic Metabolism: Cytochrome P450 (CYP) enzymes.
• Cardiac Electrophysiology Risk: QT prolongation, Torsades de Pointes, and bradycardia.