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Metformin Hydrochloride Oral tablet

What is this medicine?

METFORMIN (met FOR min) is used to treat type 2 diabetes. It helps to control blood sugar. Treatment is combined with diet and exercise. This medicine can be used alone or with other medicines for diabetes.

How should I use this medicine?

Take this medicine by mouth. Take it with meals. Swallow the tablets with a drink of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take your medicine more often than directed.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 10 years of age for selected conditions, precautions do apply.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • feeling faint or lightheaded, falls

  • low blood sugar (ask your doctor or health care professional for a list of these symptoms)

  • muscle aches or pains

  • slow or irregular heartbeat

  • unusual stomach pain or discomfort

  • unusually tired or weak

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • diarrhea

  • headache

  • heartburn

  • metallic taste in mouth

  • nausea

  • stomach gas, upset

What may interact with this medicine?

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

  • dofetilide

  • gatifloxacin

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

This medicine may also interact with the following medications:

  • digoxin

  • diuretics

  • female hormones, like estrogens or progestins and birth control pills

  • isoniazid

  • medicines for blood pressure, heart disease, irregular heart beat

  • morphine

  • nicotinic acid

  • phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine

  • phenytoin

  • procainamide

  • quinidine

  • quinine

  • ranitidine

  • steroid medicines like prednisone or cortisone

  • stimulant medicines for attention disorders, weight loss, or to stay awake

  • thyroid medicines

  • trimethoprim

  • vancomycin

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Where should I keep my medicine?

Keep out of the reach of children.

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

What should I tell my health care provider before I take this medicine?

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

  • anemia

  • frequently drink alcohol-containing beverages

  • become easily dehydrated

  • heart attack

  • heart failure that is treated with medications

  • 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

What should I watch for while using this medicine?

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

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

If you have low blood sugar, eat or drink something that has sugar. Make sure others know to get medical help quickly if you have serious symptoms of low blood sugar, like if you become unconscious or have a seizure.

If you need surgery or if you will need a procedure with contrast drugs, tell your doctor or health care professional that you are taking this medicine.

Wear a medical identification bracelet or chain to say you have diabetes, and carry a card that lists all your medications.