Diabetes mellitus biguanides

The answer is a. (Hardman, p 1510.) Although the mechanism of action of metformin and other biguanicies is unclear, biguanides virtually never cause hypoglycemia They operate independently of pancreatic p cells but are not useful in insulin-dependent diabetes mellitus (IDDM). Some possible mechanisms of action are direct stimulation of glycolysis in peripheral tissues, increased sensitivity to insulin, and reduction of glucagon levels. 

Sitagliptin is a dipeptidylpeptidase-4 inhibitor that increases insulin secretion and lowers glucagon secretion. Sitagliptin is available for oral administration. It is indicated in patients with type 2 diabetes mellitus in combination with either metformin (biguanide) or a sulphonylurea or a thiazolidinedione. 

Metformin is a biguanide used to treat diabetes mellitus. It is contraindicated in patients undergoing general anaesthesia since anaesthesia can interfere with renal function. The risk of lactic acidosis associated with metformin increases in patients with renal impairment. Metformin should be stopped before and during surgery where anaesthesia is indicated. Metformin should only be restarted after the renal function has returned to normal. 

Biguanides are used as an oral drug for the management of mild to moderately severe, noninsulin-depend-ent (type II) diabetes mellitus in obese patients who are usually above 40 years of age. It is important that for the administration of this drug the disease should have adult onset. 

Metformin hydrochloride is a biguanide that decreases blood glucose by decreasing hepatic glucose production. It may also decrease intestinal absorption of glucose and increase response to insulin. Metformin is indicated as an adjunct to diet and exercise to lower blood glucose in patients with type 2 diabetes mellitus. Metformin IR tablets and oral solution are indicated in patients 10 years of age and older. The ER tablets are indicated in patients 17 years of age and older. In combination with a sulfonylurea or insulin to improve glycemic control, metformin is indicated in patients 17 years of age and older. 

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