Sitagliptin

A DPP-4 inhibitor that improves blood glucose control without hypoglycemia.

What is Sitagliptin?

Sitagliptin is an oral antidiabetic drug belonging to the DPP-4 inhibitor class, used in type 2 diabetes mellitus.

It enhances the body’s own incretin hormones.

History & Background

Sitagliptin was the first DPP-4 inhibitor approved for clinical use, offering effective glucose control with minimal risk of hypoglycemia.

Chemical Structure & Properties

• IUPAC name: (2R)-4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine
• Molecular formula: C₁₆H₁₅F₆N₅O
• Molar mass: 407.31 g/mol
• Functional groups: Triazole, amide, fluorinated aromatic ring

Mechanism of Action

Sitagliptin lowers blood glucose by:

• Inhibiting DPP-4 enzyme
• Increasing GLP-1 and GIP levels
• Enhancing glucose-dependent insulin secretion
• Reducing glucagon release

Pharmacokinetics

• Absorption: Rapid oral absorption
• Peak plasma time: 1–4 hours
• Metabolism: Minimal hepatic metabolism
• Half-life: ~12 hours
• Excretion: Urine (unchanged)

Medical Uses

• Type 2 diabetes mellitus
• Combination therapy with metformin or insulin

Dosage Guidelines

Adults: 100 mg once daily

Renal impairment: Dose adjustment required

⚠️ Low risk of hypoglycemia when used alone.

Side Effects

• Nasopharyngitis
• Headache
• Upper respiratory tract infections
• Rare pancreatitis

Warnings & Precautions

• Monitor for signs of pancreatitis
• Adjust dose in kidney disease
• Not recommended in type 1 diabetes

Drug Interactions

• Insulin and sulfonylureas (↑ hypoglycemia risk)
• Digoxin

Frequently Asked Questions

Does sitagliptin cause hypoglycemia? – Rare.

Is it safe long-term? – Yes.

Does it cause weight gain? – No.

Can it be combined with metformin? – Yes.

⚠️ Educational content only. Not a substitute for professional medical advice.