Metformin Teva (Metformin)

• Metformin is a biguanide antidiabetic that improves glucose control in several metabolic conditions.
• Type 2 diabetes mellitus: improves glycaemic control by lowering fasting and post‑prandial blood glucose.
• Prediabetes (impaired glucose tolerance): helps delay progression to overt diabetes.
• Polycystic ovary syndrome: reduces insulin resistance and may restore ovulatory function.

• Metformin acts primarily by inhibiting hepatic gluconeogenesis through activation of AMP‑activated protein kinase (AMPK). This reduces liver glucose output and enhances insulin‑mediated glucose uptake in muscle and adipose tissue, thereby improving peripheral insulin sensitivity and lowering circulating blood glucose levels.

Metformin is generally well tolerated, but a range of adverse reactions can occur.

Common Side Effects

• Nausea
• Diarrhoea
• Abdominal discomfort
• Metallic taste
• Loss of appetite
• Flatulence

Serious or Rare Side Effects

• Lactic acidosis (potentially life‑threatening)
• Severe skin reactions such as Stevens‑Johnson syndrome
• Hepatic failure
• Hypoglycaemia when combined with other antidiabetics
• Vitamin B12 deficiency with long‑term use
• Acute pancreatitis (rare)

Metformin should be used with attention to several safety considerations.

• Renal function: assess creatinine clearance before initiation and periodically thereafter.
• Hepatic function: avoid in patients with significant liver disease due to lactic acidosis risk.
• Lactic acidosis: discontinue promptly if symptoms such as unexplained fatigue, dyspnoea, or abdominal pain develop.
• Vitamin B12 monitoring: consider periodic assessment during long‑term therapy.
• Pregnancy and lactation: use only if clearly needed after risk‑benefit evaluation.
• Store at room temperature: keep in the original container, protect from moisture and heat.

Metformin may interact with several medicines, requiring careful management.

Major Interactions (Avoid)

• Iodinated contrast media: increase risk of lactic acidosis; suspend metformin before and after imaging.
• Alcohol: potentiates lactic acidosis.
• Cimetidine: may raise metformin plasma concentrations.

Moderate Interactions (Monitor Closely)

• ACE inhibitors and ARBs: may affect renal function, requiring dose adjustment.
• Beta‑blockers: can mask hypoglycaemia symptoms.
• Diuretics: may reduce renal clearance of metformin.
• Corticosteroids: may increase blood glucose, necessitating tighter monitoring.
• Warfarin: may alter INR, requiring regular coagulation checks.