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Drug Profile

Do NOT stop taking this or any drug without the advice of your physician. Some drugs can cause severe adverse effects when they are stopped suddenly.

Limited Use [what does this mean?]
Generic drug name: glimepiride (gli MIP ear ride)
Brand name(s): AMARYL
GENERIC: not available FAMILY: Sulfonylureas
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: glipizide (GLIP i zide)
Brand name(s): GLUCOTROL, GLUCOTROL XL
GENERIC: available FAMILY: Sulfonylureas
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Limited Use [what does this mean?]
Generic drug name: glyburide (GLYE byoo ride)
Brand name(s): DIABETA, GLYNASE
GENERIC: available FAMILY: Sulfonylureas
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Do Not Use [what does this mean?]
Generic drug name: tolazamide (tole AZ a mide)
Brand name(s):
GENERIC: available FAMILY: Sulfonylureas
Find the drug label by searching at DailyMed.

Do Not Use [what does this mean?]
Generic drug name: tolbutamide (tol BYOO ta mide)
Brand name(s):
GENERIC: available FAMILY: Sulfonylureas
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

These drugs caused fetal death in animal studies. Prolonged severe hypoglycemia (4 to 10 days) has been reported in infants born to mothers who were receiving a sulfonylurea drug at time of delivery. Many experts recommend that insulin be used during pregnancy to maintain blood glucose levels. Tell your doctor if you are pregnant or thinking of becoming pregnant before you take these drugs.

Breast-feeding Warning

Sulfonylurea drugs are excreted in animal milk and cause skeletal deformities in nursing pups. They are also excreted in human milk. Since nursing infants can also become hypoglycemic, you should not breast-feed while taking these drugs.

Safety Warnings For This Drug [top]

Heat Stress Alert

This drug can affect your body’s ability to adjust to heat, putting you at risk of “heat stress.” If you live alone, ask a friend to check on you several times during the day. Early signs of heat stress are dizziness, lightheadedness, faintness, and slightly high temperature. Call your doctor if you have any of these signs. Drink more fluids (water, fruit and vegetable juices) than usual—even if you’re not thirsty—unless your doctor has told you otherwise. Do not drink alcohol.

Risk of Low Blood Sugar (Hypoglycemia) With Individual Sulfonylureas in Older People

A study has been published assessing the risk of serious hypoglycemia in diabetics over age 65 taking one of the sulfonylurea drugs.[1] The new sulfonylurea drug glimepiride was not included in the study.

Serious hypoglycemia was more than four times more frequent in those using glyburide or chlorpropamide than in users of tolbutamine. Serious hypoglycemia occurred twice as often among users of glyburide compared to those taking glipizide. Compared to tolbutamide, those taking glipizide experienced serious hypoglycemia 2.5 times more often in the study.

Listed below are the drugs taken by diabetics in the study, from glyburide, which caused the most reactions, to tolbutamide, which caused the fewest.

Frequency of Serious Hypoglycemic Reactions with Sulfonylureas
  1. glyburide
  2. chlorpropamide
  3. acetohexamide
  4. tolazamide
  5. glipizide
  6. tolbutamide

Facts About This Drug [top]

These drugs, all known as sulfonylureas, are taken by mouth (orally) to lower high blood sugar levels caused by type 2 diabetes. They work by stimulating the release of insulin from cells in the pancreas. Most type 2 diabetics can control their disease by following a prescribed diet and exercise regimen (see Diabetes: Prevention and Treatment). Oral medications are the next step if blood sugar remains uncontrolled. If you do use these drugs, it is best to use them temporarily while losing...

These drugs, all known as sulfonylureas, are taken by mouth (orally) to lower high blood sugar levels caused by type 2 diabetes. They work by stimulating the release of insulin from cells in the pancreas. Most type 2 diabetics can control their disease by following a prescribed diet and exercise regimen (see Diabetes: Prevention and Treatment). Oral medications are the next step if blood sugar remains uncontrolled. If you do use these drugs, it is best to use them temporarily while losing weight, not permanently.  

If you have type 2 diabetes, before taking any of these pills you should try following a prescribed diet for up to nine months to reduce your blood sugar levels and, if you are overweight, to lose weight. For patients who have tried and failed to control their blood sugar through diet and exercise, we recommend metformin (GLUCOPHAGE) as the best choice for initial drug treatment.

If diet and exercise combined with metformin fail to control blood sugar, patients should discuss with their doctors whether to add a second- or third-generation sulfonylurea or move directly to insulin therapy. Sulfonylureas are as effective as metformin at reducing blood sugar.[2] However, these drugs also cause weight gain, fluid retention and hypoglycemia (low blood sugar), and they have not been proven to be effective at reducing mortality when used without metformin.[2]

Do not use the first-generation sulfonylureas — tolbutamide, tolazamide and chlorpropamide (DIABINESE) — because these drugs may actually increase cardiovascular risks and mortality relative to a placebo.[3] Second- or third-generation sulfonylureas, such as glyburide and glipizide or glimepiride, have not demonstrated the same risks and are less likely to cause dangerously low blood sugar.[3]

If you are over 60 and you use a diabetes pill, your doctor should start you off at no more than half the usual adult dose.

Interactions

In October 2014, JAMA Internal Medicine published a study showing that older patients taking either glipizide or glyburide had an increased risk of severe hypoglycemia (low blood sugar) if they also took any of the following antibiotics: ciprofloxacin (CIPRO, CIPRO XR), clarithromycin (BIAXIN, BIAXIN XL), levofloxacin (LEVAQUIN), metronidazole (FLAGYL, FLAYGL ER) or the combination drug sulfamethoxazole and trimethoprim (BACTRIM, BACTRIM DS, SEPTRA, SEPTRA DS, SULFATRIM PEDIATRIC).

This increased risk was greatest for clarithromycin and least for ciprofloxacin.[4]

If you are taking glipizide or glyburide and have a bacterial infection that requires treatment with an antibiotic, you should follow these guidelines:

  • Always try to avoid taking ciprofloxacin, clarithromycin, levofloxacin, metronidazole, and sulfamethoxazole and trimethoprim. For most infections, an alternative antibiotic is available.
  • If for some reason you must take one of these five antibiotics, discuss with your doctor whether your dose of glipizide or glyburide should be temporarily reduced while taking the antibiotic.

In 2015, The British Medical Journal (BMJ) published a study showing that patients 65 years or older using glipizide or glimepiride and warfarin (COUMADIN, JANTOVEN) had an increased risk of low blood sugar (hypoglycemia). This risk was highest among patients newly started on warfarin.[5]

Before You Use This Drug [top]

Do not use if you have or have had recent:

  • severe burns or injuries
  • severe infection
  • major surgery or trauma
  • high ketone levels
  • acidosis
  • diabetic coma or ketoacidosis
  • any condition with severe changes in blood glucose levels
  • any condition that causes insulin needs to change rapidly
  • breast-feeding

Tell your doctor if you have or have had:

  • allergies to drugs, particularly to another diabetes drug, a sulfonamide (sulfa) antibiotic, or a thiazide diuretic (water pill)
  • adrenal gland disease
  • kidney or liver problems
  • thyroid disease
  • pituitary gland disease
  • recent nausea, vomiting, or high fever
  • malnutrition
  • severe diarrhea
  • delayed stomach emptying
  • intestinal obstruction
  • female hormone changes
  • severe infection
  • severe mental stress
  • heart disease and water retention (for chlorpropamide and tolbutamide)
  • pregnancy

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Call your doctor immediately and eat or drink something with sugar in it (but low in fat) if you experience symptoms of low blood sugar (see Adverse Effects, below).
  • Do not stop taking your drug without talking to your doctor.
  • If you have a high fever, nausea and vomiting, severe infection, or any severe injury, tell your doctor. Your treatment may have to be changed.
  • Do not drink alcohol. The combination of alcohol and diabetes pills may cause abdominal cramps, nausea, vomiting, headaches, flushing, and low blood sugar.
  • If you plan to have any surgery, including dental, tell your doctor that you take an oral hypoglycemic.
  • Carry medical history and medication list with you for emergency situations.
  • Wear medical identification
  • Keep quick-acting sugar and glucagon kit and needles near you.
  • Know signs of high blood sugar (see Adverse Effects, below).
  • For chlorpropamide only: Someone should check on you regularly for at least three to five days after you experience symptoms of low blood sugar.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • For extended-release glipizide tablets, swallow pills whole.
  • Do not store in the bathroom. Store pills at room temperature. Do not expose to heat, moisture, or strong light. Keep out of reach of children.
  • Stick to regime of diet, exercise, and glucose monitoring.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

The family of drugs known as monoamine oxidase (MAO) inhibitors: deprenyl, ELDEPRYL, furazolidone, FUROXONE, isocarboxazid, MARPLAN, MATULANE, NARDIL, PARNATE, phenelzine, procarbazine, selegiline, tranylcypromine.

The beta-blockers, which include propranolol (INTERAL). See list of beta-blockers.

Other drugs that can interact are: alcohol, aspirin, ATROMID-S, charcoal, chloramphenicol, CHLOROMYCETIN, cholestyramine, cimetidine, CIPRO, ciprofloxacin, clofibrate, clopidogrel, cortisone, CORTONE, dicumarol, doxepin, ECOTRIN, ESIDRIX, gemfibrozil, GENUINE BAYER ASPIRIN, hydrochlorothiazide, HYDRODIURIL, levothyroxine, LOCHOLEST, LOPID, NORVIR, oxytetracycline, PLAVIX, PRIFTIN, QUESTRAN, rifapentine, ritonavir, sertraline, SINEQUAN, sulfamethizole, SYNTHROID, TAGAMET, TERRAMYCIN, THIOSULFIL, ZOLOFT.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • signs of low blood sugar: anxiety, blurred vision, cold sweats or cool, pale skin, confusion, difficulty concentrating, drowsiness, increased hunger, headache, nausea, nervousness, nightmares and restless sleep, rapid heartbeat, shakiness, slurred speech, unsteady walk, abnormal tiredness or weakness, behavior change similar to drunkenness, weight gain
  • signs of high blood sugar: blurred vision, drowsiness, dry, flushed skin, breath smells of fruit, increased urination, loss of appetite, tiredness, abnormal thirst, deep rapid breathing, dizziness, dry mouth, headache, stomachache, nausea, vomiting
  • dark urine or pale stools
  • itching, peeling, red skin, or rash
  • yellow eyes and skin
  • sore throat and fever
  • unusual bleeding or bruising
  • weakness or tiredness
  • fainting or unconsciousness
  • coma or seizures
  • chest pain
  • chills
  • coughing up blood or increased amount of phlegm
  • skin blisters
  • sweating
  • pale skin
  • sensitivity to the sun
  • difficulty breathing
  • weight gain
  • headache

Call your doctor if these symptoms continue:

  • diarrhea
  • dizziness
  • drowsiness
  • headache
  • heartburn
  • nausea, vomiting, loss or increase in appetite
  • stomach pain
  • skin rash
  • change in sense of taste
  • constipation
  • increased volume and frequency of urination
  • blurred vision
  • increased sensitivity of skin to sunlight

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • complete blood count
  • blood levels of sugar and glycosylated hemoglobin
  • urine levels of sugar and ketones
  • chronic high blood sugar levels
  • potassium and sodium serum concentrations

last reviewed June 30, 2021