Metformin for Type 2 Diabetes

Metformin® is a prescription medicine for type 2 diabetes. It helps lower blood sugar and A1C when used with diet and exercise. You can purchase at Canadian pricing from Canada with US delivery, and you can review options even without insurance.

What Metformin Is and How It Works

At CanadianInsulin, orders are filled by licensed Canadian pharmacies after we confirm a valid prescription with your clinic. Metformin® belongs to the biguanide class. It decreases glucose production by the liver and improves insulin sensitivity in muscles. It also slows intestinal glucose absorption. These actions help reduce fasting and post-meal blood glucose. Many clinicians use metformin as first-line therapy for Type 2 Diabetes.

Metformin does not stimulate insulin release, so it typically has a low risk of hypoglycemia when used alone. It can be used alone or in combination with other glucose-lowering drugs.

Who Metformin Is For

Metformin is indicated for adults and some children with type 2 diabetes. It supports improved glycemic control alongside diet and physical activity. Clinicians also sometimes use metformin in settings of Prediabetes, Polycystic Ovary Syndrome, and Insulin Resistance when appropriate.

Patients with severe kidney disease, unstable heart failure, severe liver disease, or a history of lactic acidosis should not use metformin. Temporary pauses may be needed around certain imaging studies that use iodinated contrast or during conditions that increase dehydration or hypoxia. Always follow your prescriber’s guidance.

Dosage and Usage

Follow your prescription label exactly. The most common starting regimens include:

• Immediate-release tablets: 500 mg twice daily with meals, or 850 mg once daily with a meal.
• Extended-release tablets: 500 mg once daily, usually with the evening meal.

Doses are typically increased in small steps to improve tolerability. Titration often occurs weekly for 500 mg steps, or every two weeks for 850 mg steps. The usual maximum daily dose depends on the product. Many immediate-release products allow up to 2550 mg daily in divided doses. Many extended-release products allow up to 2000 mg daily, though some brands differ. Your prescriber will select a schedule that balances effect and tolerability.

Swallow tablets whole with food. Extended-release tablets should not be crushed or chewed. Some extended-release tablets may leave a soft, ghost-like shell in the stool; this is expected.

Strengths and Forms

Availability may vary by manufacturer and by pharmacy. Common forms include:

• Immediate-release tablets: 500 mg, 850 mg, 1000 mg.
• Extended-release tablets: 500 mg, 750 mg, 1000 mg.
• Oral solution (metformin hydrochloride): strength commonly 500 mg per 5 mL.

Both immediate-release and extended-release options can be effective. Many patients prefer extended-release tablets to reduce stomach upset. For a deeper comparison, see our guide, Metformin vs Metformin ER.

Missed Dose and Timing

If you miss a metformin dose, take it when you remember unless it is close to your next scheduled dose. If it is near the next dose, skip the missed dose. Do not double doses to catch up. Take metformin with meals to lower the chance of stomach upset. Extended-release tablets are usually taken once daily with the evening meal unless your prescriber directs otherwise.

Storage and Travel Basics

Store tablets at room temperature in a dry place away from moisture. Keep the bottle tightly closed and out of reach of children. When traveling, keep medicine in the original labeled container. Pack it in your carry-on to maintain stable conditions. For longer trips, bring extra doses and a copy of your prescription. Avoid heat, humidity, and direct sun exposure.

Benefits

Metformin offers several well-established benefits:

• Helps lower fasting and post-meal blood glucose.
• Reduces A1C when used consistently.
• Weight-neutral for many patients; some experience modest weight loss.
• Low risk of hypoglycemia when used without insulin or sulfonylureas.
• Often used as a base therapy before adding other agents.

Some studies suggest cardiovascular and metabolic benefits in certain patients. Your overall plan may include lifestyle measures, metformin, and other agents as needed.

Side Effects and Safety

Common side effects are usually gastrointestinal and often improve over time or with dose adjustments:

• Nausea or upset stomach
• Diarrhea or loose stools
• Abdominal discomfort or cramping
• Gas or bloating
• Metallic taste

Vitamin B12 levels may decrease with long-term use. Your clinician may check B12 if you have anemia or neuropathy symptoms.

Serious risks are rare but important. Lactic acidosis is a rare medical emergency, with higher risk in patients with severe kidney or liver disease, unstable heart failure, heavy alcohol use, severe infection, or hypoxia. Seek urgent care for unusual muscle pain, weakness, breathing trouble, stomach pain with nausea, or sudden worsening fatigue. Metformin may increase the risk of hypoglycemia when used with insulin or a sulfonylurea.

Drug Interactions and Cautions

Discuss all medicines and supplements with your prescriber. Notable cautions include:

• Iodinated contrast imaging: metformin may be paused around the procedure and restarted after kidney function is rechecked.
• Alcohol: excessive intake increases lactic acidosis risk.
• Topiramate and other carbonic anhydrase inhibitors: may raise acidosis risk.
• Cationic drugs (for example, certain antiarrhythmics): potential changes in metformin levels.
• Insulin or sulfonylureas: increased hypoglycemia risk when combined.

Tell your clinician about kidney or liver problems, heart failure, dehydration risk, or planned surgery or imaging.

What to Expect Over Time

Blood glucose may start improving within days. A1C typically reflects changes over several weeks. Gastrointestinal side effects often ease after dose titration or with an extended-release formulation. Weight effect is usually neutral. Your prescriber will reassess control and tolerability over time and may add another medicine if needed.

Compare With Alternatives

Several alternatives and combinations are available when intensifying therapy or improving tolerability:

• Glumetza®: an extended-release metformin brand designed for improved gastrointestinal tolerability. Useful when immediate-release causes stomach upset.
• Synjardy®: combines empagliflozin with metformin for added fasting and post-meal control. It may aid weight and blood pressure management in appropriate patients.
• DPP-4 inhibitors such as linagliptin or saxagliptin may be used with metformin when an oral add-on is desired.

For class comparisons, you can read our overview, Invokana vs Metformin. Your clinician will select options based on targets, kidney function, and side-effect profile.

Pricing and Access

You can buy metformin online with Canadian pricing, and it ships to the US. Many patients see meaningful cash-pay savings compared with local retail. Review current options and verify your prescription at checkout. If you use a health plan, you can still compare the out-of-pocket cost before you order.

To view available strengths and see your cost, check the product page and complete the steps to upload your prescription. US delivery from Canada is available after your prescription is confirmed. For periodic offers, see our Promotions page. Checkout is encrypted to protect your information.

Availability and Substitutions

Generic metformin supplies can vary by strength and manufacturer. If a specific tablet is out of stock, your prescriber may recommend a therapeutically equivalent alternative or consider an extended-release formulation when appropriate. Pharmacy teams follow your prescription and will not substitute without authorization.

Patient Suitability and Cost Saving Tips

Metformin may be a good fit if you have type 2 diabetes and intact kidney function. It may be less suitable if you have severe renal impairment, significant liver disease, unstable heart failure, frequent heavy alcohol use, or a history of lactic acidosis. Temporary pauses may be needed during acute illness, dehydration, or before certain contrast imaging studies.

Cost-saving suggestions:

• Ask your prescriber about once-daily extended-release tablets if you prefer a simpler schedule.
• Consider 90-day supplies to reduce per-fill fees and ensure continuity.
• Use combination products only when they lower overall cost and pill burden.
• Set refill reminders so you do not miss doses and lose control.
• Compare several strengths if tablet pricing differs and your daily dose allows flexibility.

Questions to Ask Your Clinician

• Is immediate-release or extended-release a better choice for my stomach tolerability and schedule?
• What starting dose and titration schedule should I follow?
• How will we monitor kidney function and vitamin B12 over time?
• Should I pause metformin before imaging with iodinated contrast?
• Which add-on medicine would you consider if A1C goals are not met?
• How should I time doses with meals to limit side effects?
• What symptoms would require urgent medical care?

Authoritative Sources

DailyMed: Metformin HCl Tablets

FDA Orange Book: Metformin Products

Health Canada Drug Product Database

Ready to get started? See current options and complete your order for prompt US delivery from Canada. This page is informational and does not replace your prescriber’s advice.