Which insulin preparation has the LONGEST duration of action and has a relatively peakless, flat pharmacokinetic profile?

• A Insulin glargine ✓
• B Insulin lispro
• C NPH insulin
• D Regular insulin

Explanation

Insulin glargine is a long-acting insulin analogue where substitution of asparagine with glycine at position A21 and addition of two arginines at the B-chain C-terminus shifts its isoelectric point to pH 6.7. After subcutaneous injection at physiological pH, it forms microprecipitates that dissolve slowly, producing a steady, peakless absorption over 20-24 hours. This mimics basal insulin secretion and minimises nocturnal hypoglycaemia compared to NPH insulin.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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