Do not take this medicine with any of the following medications:

-certain contrast medicines given before X-rays, CT scans, MRI, or other procedures
-dofetilide

This medicine may also interact with the following medications:

-acetazolamide
-alcohol
-certain antivirals for HIV or hepatitis
-certain medicines for blood pressure, heart disease, irregular heart beat
-cimetidine
-dichlorphenamide
-digoxin
-diuretics
-female hormones, like estrogens or progestins and birth control pills
-glycopyrrolate
-isoniazid
-lamotrigine
-memantine
-methazolamide
-metoclopramide
-midodrine
-niacin
-phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine
-phenytoin
-ranolazine
-steroid medicines like prednisone or cortisone
-stimulant medicines for attention disorders, weight loss, or to stay awake
-thyroid medicines
-topiramate
-trospium
-vandetanib
-zonisamide

They need to know if you have any of these conditions:

-anemia
-dehydration
-heart disease
-frequently drink alcohol-containing beverages
-kidney disease
-liver disease
-polycystic ovary syndrome
-serious infection or injury
-vomiting
-an unusual or allergic reaction to metformin, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Visit your doctor or health care professional for regular checks on your progress.

A test called the HbA1C (A1C) will be monitored. This is a simple blood test. It measures your blood sugar control over the last 2 to 3 months. You will receive this test every 3 to 6 months.

Learn how to check your blood sugar. Learn the symptoms of low and high blood sugar and how to manage them.

Always carry a quick-source of sugar with you in case you have symptoms of low blood sugar. Examples include hard sugar candy or glucose tablets. Make sure others know that you can choke if you eat or drink when you develop serious symptoms of low blood sugar, such as seizures or unconsciousness. They must get medical help at once.

Tell your doctor or health care professional if you have high blood sugar. You might need to change the dose of your medicine. If you are sick or exercising more than usual, you might need to change the dose of your medicine.

Do not skip meals. Ask your doctor or health care professional if you should avoid alcohol. Many nonprescription cough and cold products contain sugar or alcohol. These can affect blood sugar.

This medicine may cause ovulation in premenopausal women who do not have regular monthly periods. This may increase your chances of becoming pregnant. You should not take this medicine if you become pregnant or think you may be pregnant. Talk with your doctor or health care professional about your birth control options while taking this medicine. Contact your doctor or health care professional right away if you think you are pregnant.

The tablet shell for some brands of this medicine does not dissolve. This is normal. The tablet shell may appear whole in the stool. This is not a cause for concern.

If you are going to need surgery, a MRI, CT scan, or other procedure, tell your doctor that you are taking this medicine. You may need to stop taking this medicine before the procedure.

Wear a medical ID bracelet or chain, and carry a card that describes your disease and details of your medicine and dosage times.

This medicine may cause a decrease in folic acid and vitamin B12. You should make sure that you get enough vitamins while you are taking this medicine. Discuss the foods you eat and the vitamins you take with your health care professional.

Keep out of the reach of children.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Throw away any unused medicine after the expiration date.