Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Blood sugar control: Over a period of time, people may become progressively less responsive to a particular treatment for diabetes because of a worsening of their diabetes. If tolbutamide fails to lower blood glucose to target levels, the medication should be stopped and replaced, or another medication added to it. Loss of blood sugar control may occur during illness or stressful situations such as trauma or surgery. Under these conditions, your doctor may consider stopping the medication and prescribing insulin until the situation improves.
Diabetes complications: Although this medication may delay the development of complications, tolbutamide has not been shown to prevent the development of complications of diabetes. Tolbutamide must be used in addition to a proper dietary regimen and not as a substitute for diet.
Drowsiness/reduced alertness: Until your blood sugar is under control, or when changing doses of medication or when the tablets have not been taken regularly, use caution when driving or operating dangerous machinery, as alertness and reaction time may be reduced.
Low blood sugar: As with other sulfonylurea medications like tolbutamide, symptoms of hypoglycemia (low blood sugar) including dizziness, lack of energy, drowsiness, headache, and sweating have been observed with use of this medication. Weakness, nervousness, shakiness, and numbness or tingling have also been reported. Severe hypoglycemia can result from taking any of the sulfonylurea medications. Seniors, those with reduced kidney or liver function, and those who are fragile or malnourished are more likely to experience low blood sugar with these medications.
Low blood sugar is more likely to occur when food intake is inadequate or after strenuous or prolonged physical exercise. Blood glucose should be monitored regularly and emergency glucose (and glucagon kit) should be kept available in case the need arises to increase blood sugar levels.
Reaction with alcohol: Unpleasant reactions to alcohol (flushing, sensation of warmth, giddiness, nausea, and occasionally racing heart rate) may occur for people taking tolbutamide. This reaction can be prevented by avoiding the use of alcohol.
Pregnancy: Tolbutamide should not be taken by pregnant women (insulin should be used to control blood sugar). If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: Tolbutamide passes into breast milk and should not be taken by breast-feeding women. If you are a breast-feeding mother and are taking tolbutamide, it may affect your baby.