About metformin hcl
Biguanide diabetes medicine
Used for
- Type 2 diabetes, alongside diet and activity
- Sometimes used for polycystic ovary syndrome, off-label
Usual adult dose
Usually starts at 500 mg once or twice daily with meals; increased gradually as directed.
Usual dose in children
For type 2 diabetes, ages 10 and older: usually starts at 500 mg twice daily with meals; increased gradually.
Common side effects
- Diarrhea, nausea, or stomach discomfort
- Loss of appetite or altered taste
- Vitamin B12 deficiency with long-term use
- Rare but serious lactic acidosis
Important warnings
- Kidney problems increase the risk of lactic acidosis; kidney function is checked.
- May need temporary interruption around certain contrast scans or surgery.
- Excessive alcohol can increase lactic acidosis risk.
- Seek urgent care for severe weakness, breathing difficulty, unusual sleepiness, or muscle pain.
Pregnancy
Often used for diabetes during pregnancy; treatment choice depends on individual circumstances and clinician guidance.
Breastfeeding
Usually considered compatible; small amounts enter breast milk. Monitor the infant for feeding problems or unusual sleepiness.
Interactions
- Alcohol increases risk of lactic acidosis.
- Iodinated contrast media may require temporary interruption.
- Some medicines, including cimetidine and dolutegravir, can raise metformin levels.
- Certain diuretics and blood-pressure medicines can affect kidney function.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.