Not all patients with diabetes experience hypoglycemia. Those taking insulin or antidiabetes medications (e.g., sulfonylureas and meglitinides) whose side effects include hypoglycemia may experience difficulties. An appointment scheduled after a meal or snack is recommended for those patients who are at risk of hypoglycemia. Many patients with diabetes are recommended to eat a meal or snack every 4-5 hours. Those patients with gestational diabetes are recommended to eat every 2-3 hours. Dental professionals should ask patients at risk of hypoglycemia about their symptoms. Common symptoms of an alert level of hypoglycemia include shakiness, irritability, confusion and hunger, while symptoms of severe hypoglycemia include loss of consciousness, seizures and coma.

To avoid hypoglycemic episodes during a dental procedure, including a prophylaxis, blood glucose values are to be obtained. If the blood glucose level is below 70 mg/dL, then treat the patient accordingly. The patient should consume 15-20 grams of a carbohydrate source (Table 5) and retest their blood glucose level 15 minutes later. If the blood glucose value is above 70 mg/dL, the patient should consume a meal or snack to prevent recurrence of hypoglycemia before proceeding with dental treatment. If the blood glucose value is still under 70 mg/dL, repeat the treatment. Long appointments will require an additional blood glucose reading to make sure the values are not dropping below 70 mg/dL. Readings at the end of appointments are important to make sure the patient is safe to leave the office, particularly those who will be driving.

Table 5. Carbohydrate Sources for Treating Patients with Hypoglycemia (70 mg/dL or lower).6
  • 3 glucose tablets
  • 1 tube glucose gel
  • 8 hard candies (disk)
  • 2 Tbsp raisins
  • 4 oz of regular soda
  • 4 oz fruit juice
  • 8 oz skim milk


These choices will raise blood glucose values quickly. High fat foods will slow the absorption rate.

The antidiabetes medication, alpha-glucosidase inhibitors, alone does not cause hypoglycemia. However, it is usually prescribed in combination with another antidiabetic medication that causes hypoglycemia or insulin. Only a glucose or lactose food source is effective for treating hypoglycemia with this combination. The dental emergency kit should, therefore, contain a glucose (i.e., glucose tablets or gel) or a lactose (i.e., low fat or nonfat milk or yogurt) source for treatment of hypoglycemia.

If the hypoglycemic episode is severe and the patient is unable to swallow, glucagon should be administered to raise the blood glucose values. Glucagon will increase the hepatic glucose release, resulting in a release of insulin. Glucagon should also be a component of the dental emergency kit with specified or all members of the dental team having the ability to administer.