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Tolbutamide

Generic Name: tolbutamide (tole BUE ta mide)
Brand Name: Orinase, Orinase Diagnostic, Tol-Tab

Medically reviewed on March 9, 2018

What is tolbutamide?

Tolbutamide causes the pancreas to produce insulin and increases your body's response to it.

Tolbutamide is used together with diet and exercise to improve blood sugar control in adults with type 2 diabetes mellitus. Tolbutamide is not for treating type 1 diabetes.

Tolbutamide may also be used for purposes not listed in this medication guide.

Important Information

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

You should not use tolbutamide if you are allergic to tolbutamide, or if have diabetic ketoacidosis (call your doctor for treatment).

Tell your doctor if you have ever had:

  • heart disease;

  • liver or kidney disease;

  • an adrenal or pituitary gland disorder; or

  • a genetic enzyme deficiency called glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Before taking tolbutamide, tell your doctor if you have taken another oral diabetes medicine or used insulin during the past 2 weeks.

Tolbutamide may increase your risk of serious heart problems, but not treating your diabetes can also damage your heart and other organs. Talk to your doctor about the risks and benefits of this medicine.

Follow your doctor's instructions about using this medicine if you are pregnant or breast-feeding a baby. Blood sugar control is very important during pregnancy, and your dose needs may be different during each trimester of pregnancy.

Taking tolbutamide during the last 2 weeks of pregnancy may cause severe hypoglycemia in the newborn baby. Ask your doctor for a safer medicine to use during late pregnancy.

You should not breast-feed while using tolbutamide.

How should I take tolbutamide?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Your blood sugar will need to be checked often, and you may need other blood tests at your doctor's office.

Low blood sugar (hypoglycemia) can happen to everyone who has diabetes. Symptoms include headache, hunger, sweating, irritability, dizziness, nausea, and feeling shaky. To quickly treat low blood sugar, always keep a fast-acting source of sugar with you such as fruit juice, hard candy, crackers, raisins, or non-diet soda.

Your doctor can prescribe a glucagon emergency injection kit to use in case you have severe hypoglycemia and cannot eat or drink. Be sure your family and close friends know how to give you this injection in an emergency.

Blood sugar levels can be affected by stress, illness, surgery, exercise, alcohol use, or skipping meals. Ask your doctor before changing your dose or medication schedule.

Tolbutamide is only part of a complete treatment program that may also include diet, exercise, weight control, regular blood sugar testing, and special medical care. Follow your doctor's instructions very closely.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take your dose as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of tolbutamide can cause severe hypoglycemia.

Symptoms of severe hypoglycemia include extreme weakness, nausea, tremors, sweating, confusion, trouble speaking, fast heartbeats, or seizure.

What should I avoid while taking tolbutamide?

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

Tolbutamide could make you sunburn more easily. Avoid sunlight or tanning beds. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Tolbutamide side effects

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Call your doctor at once if you have:

  • dark urine, jaundice (yellowing of the skin or eyes);

  • severe skin rash, redness, or itching;

  • pale skin, easy bruising or bleeding;

  • fever, chills, sore throat, mouth sores; or

  • low levels of sodium in the body--headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady.

Older adults may be more likely to have low blood sugar while taking tolbutamide.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

Tolbutamide dosing information

Usual Adult Dose for Diabetes Type 2:

Initial dose: 1 to 2 g orally once a day or in divided doses through the day
-Adjust dose based on blood glucose response
Maintenance dose: 0.25 to 3 g orally once a day or in divided doses through the day
Maximum dose: 3 g per day

Comments: Transferring patients from other oral antidiabetic regimens should be done conservatively:
-When transferring from chlorpropamide, particular care should be exercised during the first 2 weeks due to the potential for overlapping hypoglycemic effects.
-When transferring from insulin therapy, concurrent insulin therapy should be maintained in patients requiring 20 units of insulin/day or more:
--Patients requiring 20 to 40 units of insulin/day should have insulin reduced by 30% to 50% for the first few days, and then adjust therapy based on response.
--Patients requiring more than 40 units of insulin/day should have insulin reduced by 20% the first day, and then adjust therapy based on response.

Use: As an adjunct to diet to lower blood glucose in patients with type 2 diabetes whose hyperglycemia cannot be controlled by diet alone.

What other drugs will affect tolbutamide?

Tolbutamide may not work as well when you use other medicines at the same time. Many other drugs can also affect blood sugar control. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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