Before Using This Medicine

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For glipizide and metformin the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to glipizide or metformin. Also tell your doctor and pharmacist if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Glipizide and metformin combination has not been studied in pregnant women or animals. However, independent studies with glipizide and also with metformin have not shown that either medicine causes birth defects or other problems in animal studies. It is easier during pregnancy to control your blood sugar by using injections of insulin rather than by taking oral diabetes medicines. Close control of your blood sugar can reduce the chance of your baby gaining too much weight, having birth defects, or having high blood sugar before birth. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether glipizide or metformin passes into human breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of glipizide and metformin in children with use in other age groups.

Older adults—Some older adults may be more sensitive than younger adults to the effects of these medicines. The first signs of low or high blood sugar are not easily seen or do not occur at all in older adults. This may increase the chance of low blood sugar developing during treatment. Older adults are more likely to have age-related problems and glipizide and metformin should be used carefully as age increases. This medicine should not be started in adults over 80 years of age unless kidney function is not reduced.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking glipizide and metformin, it is especially important that your doctor and pharmacist know if you are taking any of the following:

• Alcohol—Drinking alcohol may increase the risk of developing lactic acidosis and/or very low blood sugar.
  

• Beta-adrenergic blocking agents (acebutolol [e.g., Sectral], atenolol [e.g., Tenoretic, Tenormin], betaxolol [e.g., Kerlone], Bisoprolol [e.g., Zebeta, Ziac], carteolol [e.g., Cartrol], carvedilol [e.g., Coreg], labetalol [e.g., Normodyne], metoprolol [e.g., Lopressor, Toprol], nadolol [e.g., Corgard, Corzide], oxprenolol [e.g., Trasicor], penbutolol [e.g., Levatol], pindolol [e.g., Visken], propranolol [e.g., Inderal, Inderide], sotalol [e.g., Betapace, Sorine], timolol [e.g., Blocadren, Timolide])—Beta-adrenergic blocking agents can hide the symptoms of low blood sugar (hypoglycemia). Because of this, a person with diabetes might not recognize that he or she has low blood sugar and might not take immediate steps to treat it.

• Cimetidine (e.g., Tagamet) or
• Amiloride (e.g., Midamor) or
• Digoxin (e.g., Lanoxin) or
• Furosemide (e.g., Lasix) or
• Morphine (e.g., MS Contin) or
• Procainamide (e.g., Procanbid, Pronestyl) or
• Quinidine (e.g., Quinaglute, Quinidex) or
• Quinine (malaria medicine) or
• Ranitidine (e.g., Zantac) or
• Triamterene (e.g., Dyrenium) or
• Trimethoprim (e.g., Proloprim) or
• Vancomycin (e.g., Vancocin)—Use with glipizide and metformin may cause high blood levels of glipizide and metformin, which may increase the chance of low blood sugar or other side effects.

• Fluconazole (e.g., Diflucan) —Using this medicine at the same time as glipizide and metformin may cause severe low blood sugar (hypoglycemia).

Other medical problems—The presence of other medical problems may affect the use of glipizide and metformin. Make sure you tell your doctor if you have any other medical problems, especially:

• Acid in the blood (acidosis or ketoacidosis) or
• Surgery (major)—Use of insulin is best to help control diabetes in patients with these conditions.

• Blood poisoning or
• Dehydration (severe) or
• Heart or blood vessel disorders or
• Kidney disease or
• Liver disease—Lactic acidosis can occur in these conditions and chances of it occurring are even greater with a medicine that contains metformin.

• Congestive Heart Failure—Glipizide and metformin should not be used in patients who have this medical condition.

• Kidney, heart, or other problems that require medical tests or examinations that use certain medicines called contrast agents, with x-ray exams—Because this medicine contains metformin, your doctor should advise you to stop taking it before you have any medical exams or diagnostic tests that might cause less urine output than usual; you may be advised to start taking the medicine again 48 hours after the exams or tests if your kidney function is tested and found to be normal.

• Alcohol intoxication or
• Strenuous exercise not accompanied by adequate intake of food or
• Underactive adrenal gland, not properly controlled or
• Underactive pituitary gland, not properly controlled or
• Undernourished condition or
• Weakened physical condition or
• Any other condition that causes low blood sugar—Patients with these conditions may be more likely to develop low blood sugar while taking a medication that contains glipizide and metformin.

• Vitamin B₁₂ deficiency—This condition may be made worse by this medication.