Drug information provided by: IBM Micromedex
It is very important that your doctor check your progress at regular visits, especially during the first few weeks that you take this medicine. Blood and urine tests may be needed to check for unwanted effects.
Under certain conditions, too much metformin can cause a serious condition called lactic acidosis. It usually occurs when other serious health problems are present, such as a heart attack or kidney failure. The symptoms of lactic acidosis include: abdominal or stomach discomfort, decreased appetite, diarrhea, fast or shallow breathing, a general feeling of discomfort, muscle pain or cramping, and unusual sleepiness, tiredness, or weakness. If you have more than one of these symptoms together, you should get immediate emergency medical help.
Dizziness, lightheadedness, or fainting may occur with this medicine. This is more common if you have kidney disease, low blood pressure, or if you are taking a diuretic (water pill). Drinking plenty of fluids each day may help. Drink plenty of water during exercise or in hot weather. Check with your doctor if you have severe nausea, vomiting, or diarrhea that does not stop. This may cause you to lose too much water.
Ketoacidosis (high ketones and acid in the blood) may occur while you are using this medicine. This can be life-threatening and requires immediate medical attention. Your doctor may give you insulin, fluid, and carbohydrate replacement to treat this condition. Tell your doctor right away if you have nausea, vomiting, trouble breathing, increased thirst or urination.
Tell your doctor if you have bloody urine, decrease in how much or how often you urinate, painful or difficult urination, lower back or side pain, fever, chills, or swelling of the face, finger, or lower legs. These may be symptoms of a serious kidney problem.
This medicine may increase your risk of having urinary tract infections, including pyelonephritis or urosepsis. Check with your doctor right away if you have bladder pain, bloody or cloudy urine, difficult, burning, or painful urination, or lower back or side pain.
This medicine may increase your risk of having lower leg or toe amputation (leg removal surgery). Check with your doctor right away if you have pain, tenderness, sores or ulcers, or infections on your leg or foot.
This medicine can cause hypoglycemia (low blood sugar). However, low blood sugar can occur if you delay or miss a meal or snack, exercise more than usual, drink alcohol, cannot eat because of nausea or vomiting, or take certain medicines. Low blood sugar must be treated before it causes you to pass out (unconsciousness). People feel different symptoms of low blood sugar. Talk to your doctor about the best way to treat low blood sugar.
Hyperglycemia (high blood sugar) may occur if you do not take enough or skip a dose of your diabetes medicine, overeat or do not follow your diet plan, have a fever or infection, or do not exercise as much as usual. High blood sugar can be very serious and must be treated right away. It is important that you learn which symptoms you have in order to treat it quickly. Talk to your doctor about the best way to treat high blood sugar.
This medicine may cause vaginal yeast infections in women and yeast infections of the penis in men. This is more common in patients who have a history of genital yeast infections or in men who are not circumcised. Women may have a vaginal discharge, itching, or odor. Men may have redness, itching, swelling, or pain around the penis, or a discharge with a strong odor from the penis. Check with your doctor right away if you have any of these symptoms.
This medicine may cause a rare but serious bacterial infection, called necrotizing fasciitis of the perineum or Fournier's gangrene, which can cause damage to the tissue under the skin in the area between and around the anus and genitals (perineum). Fournier's gangrene may lead to hospitalization, multiple surgeries, or death. Check with your doctor right away if you have fever, unusual tiredness or weakness, or pain, tenderness, redness, or swelling of the area between and around your anus and genitals.
This medicine may cause some women who do not have regular monthly periods to ovulate. This can increase the chance of pregnancy. If you are a woman of childbearing potential, you should discuss birth control options with your doctor.
Let your doctor or dentist know you are using this medicine. Your doctor may advise you to stop using this medicine at least 4 days before you have major surgery or diagnostic tests, especially tests that use a contrast dye.
Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests (eg, urine glucose tests may not be accurate).
Do not drink a lot of alcohol while you are using this medicine. Heavy alcohol use can increase your risk for lactic acidosis.
There may be a time when you need emergency help for a problem caused by your diabetes. You need to be prepared for these emergencies. It is a good idea to wear a medical identification (ID) bracelet or neck chain at all times. Also, carry an ID card in your wallet or purse that says you have diabetes with a list of all your medicines.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.