Generic Name: Tolbutamide

  • What is Tolbutamide?

    Tolbutamide is an oral medication that, added to a proper diet, lowers blood sugar (glucose) levels in patients with type 2 diabetes who cannot control their glucose levels with diet alone.

  • What is the most important information I should know about Tolbutamide?

    Always remember that tolbutamide is an aid to helping to control your glucose (sugar) levels. It is not a substitute for a good diet and exercise.

    Tolbutamide may cause severe lowering of blood sugar (hypoglycemia). There is a greater risk of hypoglycemia if you have kidney or liver problems; are elderly, debilitated, or malnourished; have adrenal or pituitary problems; don't eat enough; exercise too much; drink alcohol; or use multiple diabetes medications.

    Loss of blood sugar control may occur when exposed to stress such as trauma, fever, infection, or surgery. Insulin may be necessary.

    The effectiveness of tolbutamide and all antidiabetic drugs may decrease over time from disease progression.

    Tolbutamide may cause hemolytic anemia (a destruction of red blood cells) in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency.

    Taking tolbutamide may increase your risk of developing heart problems.

    If you are taking tolbutamide, you should check your blood or urine periodically for abnormal glucose levels.

  • Who should not take Tolbutamide?

    You should not take tolbutamide if you have had an allergic reaction to it.

    Do not take tolbutamide if you are suffering from 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).

    In addition, tolbutamide should not be used as the sole therapy in treating type 1 diabetes.

  • What should I tell my doctor before I take the first dose of Tolbutamide?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with tolbutamide. Also, talk to your doctor about your complete medical history, especially if you have kidney disease, liver disease, thyroid disease, type 1 diabetes, diabetic ketoacidosis, heart problems, G6PD deficiency, a serious infection, illness, injury, or need surgery.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Dosage levels are based on individual needs.

    Adults: Usually, an initial daily dose of 1-2 grams (g) is recommended. Maintenance therapy usually ranges from 0.25-3 g daily. Daily doses >3 g are not recommended.

    Older adults: Older, malnourished, or debilitated people, or those with impaired kidney or liver function, are usually prescribed lower initial and maintenance doses to minimize the risk of hypoglycemia.

  • How should I take Tolbutamide?

    Tolbutamide is usually taken in the morning if it is taken once a day, or throughout the day if taken in divided doses. Follow your doctor's instructions if you develop stomach upset while on tolbutamide.

  • What should I avoid while taking Tolbutamide?

    Avoid alcohol. It lowers blood sugar and may interfere with your diabetes treatment.

  • What are possible food and drug interactions associated with Tolbutamide?

    If tolbutamide 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 tolbutamide with the following: alcohol, beta-adrenergic blocking agents such as propranolol and metoprolol, calcium channel blockers such as diltiazem and verapamil, chloramphenicol, corticosteroids such as prednisone, coumarins such as warfarin, estrogens, isoniazid, miconazole, monoamine oxidase inhibitors such as phenelzine, nicotinic acid, nonsteroidal anti-inflammatory drugs such as ibuprofen and naproxen, oral contraceptives, phenothiazines such as chlorpromazine, phenytoin, probenecid, salicylates such as aspirin, sulfonamides such as sulfisoxazole, sympathomimetics such as albuterol, thiazides and other diuretics such as hydrocholorothiazide and furosemide, or thyroid products.

  • What are the possible side effects of Tolbutamide?

    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 this drug.

    Side effects may include: hypoglycemia, GI disturbances (eg, nausea, abdominal fullness [epigastric fullness], heartburn), decreased white blood cell levels (leukopenia), failure of bone marrow to make white blood cells (agranulocytosis), enzyme deficiency of the liver (hepatic porphyria), low blood sodium levels (hyponatremia)

  • Can I receive Tolbutamide if I am pregnant or breastfeeding?

    The effects of tolbutamide during pregnancy are unknown. Tell your doctor immediately if you are pregnant, or plan to become pregnant. Tolbutamide is not recommended for treatment of diabetes in pregnant women. If prescribed, stop tolbutamide at least 2 weeks before the expected delivery date. Your doctor may prescribe insulin during pregnancy to control blood sugar levels.

    You should not breastfeed while on therapy with tolbutamide. If you are planning to breastfeed, your doctor may stop your tolbutamide and start you on insulin therapy.

  • What should I do if I miss a dose of Tolbutamide?

    If you miss a dose of tolbutamide, take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store Tolbutamide?

    Store at room temperature, away from light.

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