METFORMIN

 

ACTIONS AND USES: Metformin is a preferred oral antidiabetic drug for managing type 2 DM because of its effectiveness and safety. It is used alone or in combination with other antidiabetic medications or insulin. It is approved for use in children age 10 or above. It is available as regular-release tablets, solution, and sustained-release forms. Metformin reduces fasting and postprandial glucose levels by decreasing the hepatic production of glucose by the process of gluconeogenesis and reducing insulin resistance. It does not promote insulin release from the pancreas. A major advantage of the drug is that it does not cause hypoglycemia. The drug's actions do not depend on stimulating insulin release, so it is able to lower glucose levels in patients who no longer secrete insulin. In addition to lowering blood glucose levels, it lowers triglyceride and total and low-density lipoprotein (LDL) cholesterol levels, and it promotes weight loss. Metformin reduces insulin resistance, which in turn lowers insulin and androgen levels, thus restoring normal menstrual cycles and ovulation.

ADMINISTRATION ALERTS: Sustained-release tablets must be swallowed whole and not crushed or chewed. Fasting blood glucose levels should be obtained every 3 months, and the dose adjusted accordingly. Discontinue the medication immediately if signs of acidosis are present. Pregnancy category B.

PHARMACOKINETICS: Onset Peak Duration Less than 1 h 1–3 h (regular release); 4–8 h (extended release) 12 h (regular release); 24 h (extended release)

ADVERSE EFFECTS: The most common adverse effects are GI related and include nausea, vomiting, abdominal discomfort, metallic taste, diarrhea, and anorexia. It may also cause headache, dizziness, agitation, and fatigue. Unlike the sulfonylureas, metformin rarely causes hypoglycemia or weight gain.

Warning: Lactic acidosis is a rare, though potentially fatal, adverse effect. The risk for lactic acidosis is increased in patients with renal insufficiency or any condition that puts them at risk for increased lactic acid production, such as liver disease, severe infection, excessive alcohol intake, shock, or hypoxemia.

RELATED;

1. DIABETES MELLITUS

2. INSULIN

3.  PATHOPHYSIOLOGY OF DIABETES

4.  PHARMACOLOGY AND THERAPEUTICS