Metformin is usually taken by mouth as a pill or a liquid once, twice, or three times a day. Metformin should be taken with meals to avoid stomach upset.  

There are two types of metformin:

  • Immediate-release, sometimes shortened to IR
  • Extended-release, sometimes shortened to ER or XR

Immediate-release starts working right away. It’s usually taken once or twice a day. Some people who take a high dose may take it three times a day.

Extended-release takes longer to start working and lasts longer in your body. It’s usually taken once a day with dinner. These pills should not be cut, crushed, or chewed. Crushing them can make them less effective.

If you take liquid metformin, it’s important to take the right amount. The best way to do that is to measure your dose with a marked spoon or cup.

Metformin comes in many doses. Most people start by taking the lowest dose, 500 mg. If your blood sugar is still too high, your doctor may increase the dose. Your doctor will work with you to find a dose that works well for you. Always talk to your doctor before making any changes to your medicine.