Information on Tablets A-Z
Generic name: Metformin hydrochloride
Why is this drug prescribed: Glucophage is an oral antidiabetic medication used to treat type 2 (non-insulin-dependent) diabetes. Diabetes develops when the body proves unable to burn sugar and the unused sugar builds up in the bloodstream. Glucophage lowers the amount of sugar in your blood by decreasing sugar production and absorption and helping your body respond better to its own insulin, which promotes the burning of sugar. It does not, however, increase the body's production of insulin. Glucophage is sometimes prescribed along with insulin or certain other oral antidiabetic drugs such as Micronase or Glucotrol. It is also used alone. Standard Glucophage tablets are taken two or three times daily. An extended-release form (Glucophage XR) is available for once-daily dosing.
Most important fact about this drug: Always remember that Glucophage is an aid to, not a substitute for, good diet and exercise. Failure to follow a sound diet and exercise plan can lead to serious complications such as dangerously high or low blood sugar levels. Remember, too, that Glucophage is not an oral form of insulin and cannot be used in place of insulin.
How should you take this medication: Do not take more or less of this medication than directed by your doctor. The drug should be taken with food to reduce the possibility of nausea or diarrhea, especially during the first few weeks of therapy. If taking Glucophage XR, be sure to swallow the tablet whole; do not crush it or chew it. The inactive ingredients in the tablet may occasionally appear in the stool. This is not a cause for concern. --If you miss a dose... Take it as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Never take 2 doses at the same time. --Storage instructions... Store it at room temperature.
What side effects may occur: Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Glucophage. If side effects from Glucophage occur, they usually happen during the first few weeks of therapy. Most side effects are minor and will go away after you've taken Glucophage for a while. More common side effects may include: Abdominal discomfort, diarrhea, gas, headache, indigestion, nausea, vomiting, weakness Less common side effects may include: Abdominal distention, abnormal stools, altered sense of taste, chest discomfort, chills, constipation, dizziness, flu-like symptoms, flushing, increased sweating, low blood sugar, light-headedness, muscle pain, nail disorders, pounding heartbeat, rash, shortness of breath, upper respiratory infection Glucophage, unlike other oral antidiabetics, does not usually cause hypoglycemia (low blood sugar). However, hypoglycemia remains a possibility, especially in older, weak, and undernourished people and those with kidney, liver, adrenal, or pituitary gland problems. The risk of hypoglycemia increases when Glucophage is combined with other diabetes medications. The risk is also boosted by missed meals, alcohol, and excessive exercise. To avoid hypoglycemia, you should closely follow the dietary and exercise plan suggested by your physician. If you feel hypoglycemia coming on, get some fast-acting sugar, such as a 4 to 6 ounce glass of fruit juice. Glucophage can cause a serious side effect called lactic acidosis, a buildup of lactic acid in the blood. This problem is most likely to occur in people whose liver or kidneys are not working well, and in those who have multiple medical problems, take several medications, or have congestive heart failure. The risk also is higher if you are an older adult or drink alcohol. Although the condition is rare, it can be fatal. Lactic acidosis is a medical emergency that must be treated in a hospital. Symptoms of lactic acidosis may include: Feeling very weak, tired, or uncomfortable, feeling cold, dizzy, or light-headed, increasing sleepiness, muscle pain, slow or irregular heartbeat, trouble breathing, unexpected or unusual stomach discomfort (especially if you already have been taking Glucophage for a while) If you notice these symptoms, stop taking Glucophage and call your doctor right away.
Why should this drug not be prescribed: Avoid Glucophage if it has ever given you an allergic reaction. If you have congestive heart failure, do not take Glucophage. This condition increases your risk of developing lactic acidosis. Do not take Glucophage if you are suffering from acute or chronic metabolic acidosis, including diabetic ketoacidosis (a life-threatening medical emergency caused by insufficient insulin and marked by excessive thirst, nausea, fatigue, pain below the breastbone, and fruity breath). You should not take Glucophage for 2 days before and after having an X-ray procedure with an injectable contrast agent (radioactive iodine). Also, if you are going to have surgery, except minor surgery, you should stop taking Glucophage. Once you have resumed normal food and fluid intake, your doctor will tell you when you can go back to therapy with Glucophage. If you have kidney or liver disease or develop serious conditions such as a heart attack, severe infection, or a stroke, do not take Glucophage. You should not take Glucophage if you are seriously dehydrated, having lost a large amount of fluid from severe vomiting, diarrhea, or high fever. If you lose control of your blood sugar due to the stress of a fever, injury, infection, or surgery, your doctor may temporarily take you off of Glucophage and ask you to take insulin instead.
Special warnings about this medication: Before you start therapy with Glucophage, and at least once a year thereafter, your doctor will do a complete assessment of your kidney function. If you develop kidney problems while on Glucophage, your doctor will discontinue this medication. If you are an older person, you will need to have your kidney function monitored more frequently, and your doctor may want to start you at a lower dosage. If you are taking Glucophage, you should check your blood or urine periodically for abnormal sugar (glucose) levels. Your doctor will do annual blood checks to see if Glucophage is causing a vitamin B12 deficiency or any other blood problem. It's possible that drugs such as Glucophage may lead to more heart problems than diet treatment alone, or diet plus insulin. If you have a heart condition, you may want to discuss this with your doctor. The effectiveness of any oral antidiabetic, including Glucophage, may decrease with time. This may be due to either a diminished responsiveness to the medication or a worsening of the diabetes.
Possible food and drug interactions when taking this medication: If Glucophage is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Glucophage with the following: Amiloride (Moduretic) Calcium channel blockers (heart medications) such as Calan, Isoptin, and Procardia Cimetidine (Tagamet) Decongestant, airway-opening drugs such as Sudafed and Ventolin Digoxin (Lanoxin) Estrogens such as Premarin Furosemide (Lasix) Isoniazid (Rifamate), a drug used for tuberculosis Major tranquilizers such as Thorazine Morphine Niacin (Niaspan) Oral contraceptives Phenytoin (Dilantin) Procainamide (Procanbid, Pronestyl) Quinidine (Quinidex) Quinine Ranitidine (Zantac) Steroids such as prednisone (Deltasone) Thyroid hormones (Synthroid) Triamterene (Dyazide, Dyrenium) Trimethoprim (Bactrim, Septra) Vancomycin (Vancocin) Water pills (diuretics) such as HydroDIURIL, Dyazide, and Moduretic Do not drink too much alcohol, since excessive alcohol consumption can cause low blood sugar and alcohol enhances some effects of this drug.
Special information if you are pregnant or breastfeeding: If you are pregnant or plan to become pregnant, tell your doctor immediately. Glucophage should not be taken during pregnancy. Since studies suggest the importance of maintaining normal blood sugar (glucose) levels during pregnancy, your doctor may prescribe insulin injections instead. It is not known whether Glucophage appears in human breast milk. Therefore, women should discuss with their doctors whether to discontinue the medication or to stop breastfeeding. If the medication is discontinued and if diet alone does not control glucose levels, then your doctor may consider insulin injections.
Recommended dosage: Your doctor will tailor your dosage to your individual needs. ADULTS: Glucophage The usual starting dose is one 500-milligram tablet twice a day, taken with morning and evening meals. Your doctor may increase your daily dose by 500 milligrams at weekly intervals, based on your response up to a total of 2,000 milligrams. An alternative starting dose is one 850-milligram tablet a day, taken with the morning meal. Your doctor may increase this by 850 milligrams at 14-day intervals, to a maximum of 2,550 milligrams a day. The usual maintenance dose ranges from 1,500 to 2,550 milligrams daily. If you take more than 2,000 milligrams a day, your doctor may recommend that the medication be divided into three doses, taken with each meal. Glucophage XR The usual starting dose is one 500-milligram tablet once daily with the evening meal. Your doctor may increase your dose by 500 milligrams at weekly intervals, up to a maximum dosage of 2,000 milligrams a day. If a single 2,000-milligram dose fails to control your blood sugar, you may be asked to take 1,000-milligram doses twice a day. If you need more than 2,000 milligrams a day, the doctor will switch you to regular Glucophage. CHILDREN: Glucophage For children 10 to 16 years old, the usual starting dose is one 500-milligram tablet twice a day with meals. The dosage may be increased by 500 milligrams at weekly intervals up to a maximum of 2,000 milligrams daily. Glucophage has not been tested in children younger than 10. Glucophage XR This form of the drug has not been tested in children younger than 17. OLDER ADULTS: Older people and those who are malnourished or in a weakened state are generally given lower doses of Glucophage because their kidneys may be weaker, making side effects more likely.
Overdosage: An overdose of Glucophage can cause lactic acidosis. (See "What Side Effects May Occur?") If you suspect a Glucophage overdose, seek emergency treatment immediately.