Metformin Morningside Healthcare (Metformin Hydrochloride)

Metformin is indicated for conditions related to abnormal glucose metabolism.

• Type 2 diabetes mellitus: improves glycemic control by lowering fasting and post‑prandial blood glucose levels.
• Prediabetes (impaired glucose tolerance): helps delay progression to type 2 diabetes by improving insulin sensitivity.
• Polycystic ovary syndrome (off‑label): may reduce insulin resistance and assist in menstrual regularity.

• Metformin acts primarily by inhibiting mitochondrial respiratory‑chain complex I, which reduces hepatic gluconeogenesis. It also decreases intestinal absorption of glucose and increases peripheral glucose uptake through activation of AMP‑activated protein kinase (AMPK), thereby improving insulin sensitivity and lowering circulating blood glucose levels.

Metformin may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Gastrointestinal upset: nausea, abdominal discomfort, and loss of appetite.
• Diarrhea: frequent loose stools, especially during treatment initiation.
• Metallic taste: transient alteration of taste perception.
• Flatulence: increased intestinal gas.
• Weight loss: modest reduction in body weight.
• Vitamin B12 reduction: gradual decline with long‑term therapy.

Serious or Rare Side Effects

• Lactic acidosis: rare but life‑threatening metabolic acidosis.
• Severe hypoglycemia: uncommon, usually when combined with insulin or sulfonylureas.
• Hepatic dysfunction: elevated liver enzymes in susceptible individuals.
• Skin rash: hypersensitivity reactions including Stevens‑Johnson syndrome.
• Eosinophilic pneumonia: rare pulmonary inflammation.
• Anemia: occasional reduction in hemoglobin levels.

Metformin requires careful patient assessment and monitoring to minimize risks.

• Renal function assessment: evaluate eGFR before initiation and periodically during therapy.
• Lactic acidosis risk: avoid in patients with severe renal or hepatic impairment.
• Vitamin B12 monitoring: consider periodic assessment during long‑term use.
• Pregnancy and lactation: use only if benefits outweigh risks.
• Drug interactions: review concomitant medications for potential interactions.
• Store at ambient temperature: keep below 25°C, protect from moisture and light in original container.

Metformin interacts with several medicines that can alter its safety or efficacy.

Major Interactions (Avoid)

• Iodinated contrast agents: may precipitate acute renal failure; discontinue metformin before and after imaging.
• Cimetidine: can increase metformin plasma levels, raising risk of lactic acidosis.
• Alcohol abuse: potentiates lactic acidosis risk.

Moderate Interactions (Monitor Closely)

• Beta‑blockers: may mask hypoglycemia symptoms.
• Diuretics (loop, thiazide): can affect renal clearance of metformin.
• Corticosteroids: may increase blood glucose, requiring dose adjustment.