A patient on sitagliptin (DPP-4 inhibitor) also takes an ACE inhibitor. The combination increases risk of which adverse effect?

• A Severe hypoglycaemia
• B Lactic acidosis
• C Urinary tract infections
• D Angioedema ✓

Explanation

DPP-4 not only degrades GLP-1 and GIP but also cleaves bradykinin and substance P. Inhibiting DPP-4 slows bradykinin degradation; ACE inhibitors also block bradykinin degradation. Combined DPP-4 inhibition plus ACEi causes additive bradykinin accumulation, significantly increasing the risk of angioedema. This pharmacodynamic interaction is clinically important. DPP-4 inhibitors alone do not cause hypoglycaemia; lactic acidosis is a concern with metformin (not DPP-4 inhibitors); UTIs are associated with SGLT2 inhibitors.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.