Metformin is a medicine used in patients
with Type 2 Diabetes. It is used with a
"healthy eating" meal plan and exercise.
Metformin may also be taken with other
Metformin lowers blood sugar in these
ξ Helps muscle cells use sugar
ξ Lowers the amount of sugar the liver
ξ Lowers how much sugar the body
absorbs from the food you eat.
Metformin does not increase how much
insulin the body makes.
How Medication is Supplied
Glucophage® (Metformin Regular Release)
ξ 500 mg, 850 mg, 1000 mg tablets
Fortamet®, Glucophage XR®, Glumetza®
(Metformin Extended Release)
ξ 500 mg, 750 mg, 1000 mg tablets
Riomet® (Metformin Regular Release)
ξ 500 mg/5 mL solution
You will take metformin one to three times
every day. You will take it with food or after
you eat. Follow the directions on your
Metformin is usually started at a low dose.
The dose is increased over one or two
weeks. This makes stomach upset less
Most patients take 1500 mg to 2000 mg of
metformin every day.
Metformin extended release tablets must be
swallowed whole. Never crush or chew
You may see part of the extended release
tablet in your stool. This is the outer shell of
the tablet. Do not take an extra dose if this
Do not stop taking metformin on your own.
Keep taking it even if you feel well. Keep
taking it if your blood sugars improve.
If you miss a dose of this medicine, take it
with food as soon as you can. Skip the
missed dose if it is almost time for your next
dose. Do not take two doses at once.
What You Should Know Before You
Your doctor will order lab tests while you
take this medicine. The labs may include:
kidney function, fasting blood glucose,
hemoglobin A1c, and complete blood cell
counts. Lab tests help monitor your diabetes.
Lab tests help check for side effects of the
Keep all doctor and lab appointments.
Wear a medical alert bracelet or necklace.
Let your doctor know if:
You have congestive heart failure
You are pregnant, planning on becoming
pregnant, or breastfeeding.
You are having a body scan or x-ray that
uses dye. Metformin may need to be
stopped for a few days.
You are having surgery. Metformin may
need to be stopped for a few days.
Tell your doctor and pharmacist about your
medicines. This includes prescription and
over the counter medicines. Also tell them
about herbal and vitamin products. Tell
them about all of your health problems
The most common side effects of metformin
are nausea or stomach upset, diarrhea,
bloating, and decreased appetite. The side
effects should go away within one or two
weeks. The side effects may come back if
your dose is increased.
Take metformin with food or after a meal to
have fewer side effects.
Contact your health care team if the side
effects do not get better. Contact them if you
have a change in your health.
Metformin should not cause low blood sugar
if it is your only diabetes medicine.
Metformin can cause lactic acidosis. Lactic
acidosis is a rare but severe problem. It
happens when lactic acid builds up in the
blood. Your risk having lactic acidosis is
low if you have healthy kidneys and liver.
Here are some things that may increase your
Severe kidney or liver problems.
Drinking large amounts of alcohol every
Binge alcohol drinking
Severe congestive heart failure
Illness (vomiting, diarrhea, fever)
Lactic acidosis can make you feel weak or
tired. Your muscles may ache. You may
have trouble breathing. Your stomach may
hurt or you may have cramps. You may feel
cold and your heart beat may change. You
may feel dizzy or faint. Call your doctor at
once if you have these symptoms while
you are taking metformin.
Your health care team may have given you this information as part of your care. If so, please use it and call if you
have any questions. If this information was not given to you as part of your care, please check with your doctor. This
is not medical advice. This is not to be used for diagnosis or treatment of any medical condition. Because each
person’s health needs are different, you should talk with your doctor or others on your health care team when using
this information. If you have an emergency, please call 911. Copyright © 10/2016 University of Wisconsin Hospitals
and Clinics Authority. All rights reserved. Produced by the Department of Nursing HF#4912.