Metformin Side Effects
Common and serious side effects of Metformin (Metformin Hydrochloride) — what to expect and how to manage them.
Common Side Effects
- Diarrhea
- Nausea
- Stomach upset or cramping
- Gas and bloating
- Metallic taste in mouth
- Loss of appetite
- Heartburn
Serious Side Effects
Seek immediate care if severe- Lactic acidosis (rare but serious — risk with kidney impairment, liver disease, heart failure, or contrast dye)
- Vitamin B12 deficiency (long-term use, especially >4 years)
- Low blood sugar when combined with insulin or sulfonylureas
Managing Side Effects
- Take with meals to reduce GI side effects — this is the #1 tip
- Extended-release (Glucophage XR) causes significantly less diarrhea
- Hold for 48 hours after IV contrast dye until kidney function confirmed normal
- Annual B12 checks after 4+ years of use
What Your Doctor May Monitor
Kidney function (eGFR) — contraindicated if <30, reduce dose if 30-45B12 levels annuallyBlood glucose and HbA1c
Metformin Cash Price
Metformin cash prices start from $14 when pharmacies compete on Script Unlock — up to 70% below retail. No insurance required.
Compare Metformin PricesMedical Disclaimer: This information is for educational reference only. Side effects vary by individual, dose, and other medications. Always consult your healthcare provider for personalized medical advice. Do not stop or change your medication without medical guidance.