Guidelines for the Selection of Hypoglycemic Drugs in Patients with Hyperglycemia: Types, Dosage, and Adjustment Principles

Medication Use and Dosage Considerations for Hyperglycemic Patients:

Correct Selection of Hypoglycemic Drugs:

Due to significant differences in the characteristics, efficacy, and indications of various hypoglycemic drugs, improper selection can easily lead to side effects. Therefore, diabetic patients must use medication rationally under the guidance of a doctor, addressing the specific symptoms.

(1) Selection of Oral Hypoglycemic Drugs for Newly Diagnosed Diabetic Patients

If a patient presents with typical polydipsia, polyuria, polyphagia, and weight loss upon initial diagnosis, a simple diet therapy is unnecessary. In the absence of ketonuria, oral sulfonylurea hypoglycemic drugs can be started immediately, combined with dietary control.

If a patient is asymptomatic or has very mild symptoms after initial diagnosis, a simple diet therapy for one month can be initiated, combined with exercise therapy. If blood sugar does not decrease after one month, medication can be selected based on the situation. Specifically, the following two situations apply:

① For non-obese patients, if fasting blood glucose remains above 11.1 mmol/L (200 mg/dL) after one month of simple diet therapy, sulfonylurea hypoglycemic drugs can be started.

The initial dose should be determined based on the presence or absence of symptoms and blood sugar levels. For patients without diabetic symptoms and with fasting blood glucose below 11.1 mmol/L (200 mg/day), glibenclamide 2.5 mg/day, glibenclamide 80 mg/day, or sulfadiazine 5 mg/day can be used. If control is unsatisfactory after one week of treatment, the dosage should be rapidly increased. For patients with typical diabetic symptoms, blood glucose is generally above 13.9 mmol/L (250 mg/day), a stronger hypoglycemic agent should be chosen at a higher dosage, i.e., glibenclamide 7.5–15 mg/day, or sulfadiazine 30 mg/day.

② For obese patients, if fasting blood glucose is higher than 11.1 mmol/L after one month of dietary therapy, biguanides or acarbose can be started; if fasting blood glucose remains higher than 11.1 mmol/L after two weeks of treatment, sulfonylureas can be added; if fasting blood glucose is higher than 16.7 mmol/L (300 mg/day), sulfonylurea treatment should begin for 7-10 days. If blood glucose does not decrease significantly, biguanides or acarbose should be added.

(2) Adjusting oral hypoglycemic agents during treatment: The primary goal of diabetes medication is to achieve fasting blood glucose below 11.1 mmol/L. Once this goal is achieved, the next goal is to achieve a second goal: 2-hour postprandial blood glucose below 11.1 mmol/L. If the maximum dose of one oral hypoglycemic agent is reached and strict dietary control fails to achieve both goals, a combination of two oral hypoglycemic agents is necessary. For adjusting hypoglycemic medications in asymptomatic patients, whether adding a biguanide or acarbose from the maximum dose of sulfonylureas, or vice versa, the dosage should start small and gradually increase to the maximum. Simultaneously, if combination therapy is already in place and fasting blood glucose is below 11.1 mmol/L, but postprandial 2-hour blood glucose does not reach this level, insulin therapy is generally not considered initially. Instead, dietary adjustments, increased physical activity, and the consumption of high-fiber foods and smaller, more frequent meals are necessary to lower postprandial blood glucose. Once blood glucose levels reach the target and the condition is satisfactorily controlled, one of the two medications can be reduced; if only one medication is used, it can be discontinued. Adjustments can be made repeatedly based on the patient's condition.

For patients with severe symptoms but no ketosis, adjustments to hypoglycemic medications should be made on a case-by-case basis. Insulin therapy is generally used in the following situations:

Significant weight loss or emaciation;

No significant weight loss, but symptoms do not improve after one week of treatment with the maximum dose of sulfonylureas;

Fasting blood glucose levels higher than 19.4 mmol/L (350 mg/dL);

Obese patients in good general condition with negative chest X-ray and blood/urine tests, but who start with half the maximum dose of sulfonamides, show no improvement after one week, and are then rapidly increased to the maximum dose, but still show no improvement after one week;

After one week of treatment with the maximum dose of sulfonamides, the condition improves, but after another 1-2 weeks of observation, no further improvement is seen, and significant symptoms persist.

Of course, the above are just some common principles for medication selection. In actual treatment, due to the variability of the condition and the influence of various factors, the selection of hypoglycemic drugs becomes complex and requires caution. Therefore, diabetic patients should not choose hypoglycemic drugs on their own, but should choose them under the guidance of a doctor.