Insulin lispro acts faster than regular human insulin after subcutaneous injection because:

• A It is conjugated with a fatty acid that binds serum albumin
• B Its phenol-mediated hexamer formation accelerates dimer dissociation
• C It forms micro-precipitates at the injection site that slowly dissolve
• D Reversal of two amino acids near the C-terminal of the B chain reduces hexamer self-association ✓

Explanation

Lispro is produced by swapping the positions of lysine at D29 and proline at D28 on the insulin D chain. This reversal destabilizes the tendency of insulin molecules to pair as dimers and assemble into hexamers, so monomers are absorbed rapidly through the capillary endothelium after subcutaneous injection. Option A describes detemir and degludec, option C describes glargine, and option B states the opposite of the true structural change.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.