Drug–Drug and Drug–Disease Interactions Across Antidiabetic Drug Classes: A Narrative Review and Practical Recommendations

Background: The pharmacological management of type 2 diabetes mellitus has become increasingly complex due to expanding therapeutic options and the high prevalence of multimorbidity in affected patients. As a result, the risk of drug–drug and drug–disease interactions has grown significantly, with potential implications for glycemic control, safety, and treatment outcomes. Objective: This narrative review provides a comprehensive, class-based overview of clinically relevant interactions associated with antidiabetic medications, highlighting their mechanisms, clinical consequences, and practical management strategies. Methods: A targeted literature search was conducted using major medical databases to identify clinical studies, meta-analyses, pharmacovigilance reports, and evidence-based guidelines concerning interactions related to key antidiabetic drug classes. Interactions were categorized as pharmacokinetic, pharmacodynamic, or disease-related. Results: Significant variability exists across antidiabetic drug classes in terms of interaction profile and clinical relevance. Metformin presents interaction risks mainly through renal impairment or co-administration with drugs affecting lactate metabolism. Sulfonylureas and glinides are strongly associated with hypoglycemia-enhancing interactions. DPP-4 inhibitors generally exhibit a low interaction burden, whereas GLP-1 receptor agonists may interact through delayed gastric emptying. SGLT2 inhibitors require caution in patients with diuretics or conditions predisposing them to dehydration or ketoacidosis. Insulin remains highly sensitive to pharmacodynamic interactions with a broad spectrum of therapies. Underlying renal, hepatic, and cardiovascular conditions further modify the interaction risk. Conclusions: Understanding class-specific interaction profiles is essential for personalized and safe diabetes management. Careful medication review, close metabolic monitoring, and individualized dose adjustments can mitigate the risk of harmful interactions. Further research is needed to elucidate interactions in populations with advanced multimorbidity and polypharmacy.