Drug-induced hypoglycemia

Definition

Drug-induced hypoglycemia is low blood sugar that results from medication.

Causes

Even when diabetes is managed very carefully, the medications used to treat diabetes can result in drug-induced hypoglycemia. Missing meals, drinking alcohol, too much activity, and intentional or unintentional overdose of medications used to treat diabetes can all cause blood glucose levels to drop.

The condition may also occur when someone without diabetes takes a medicine used to treat diabetes. In rare cases, non-diabetes-related medicines may cause hypoglycemia.

Medications that can cause drug-induced hypoglycemia include:

• Insulin
• Sulfonylureas
• Metformin when used with sulfonylureas
• Pentamidine
• Quinidine
• Quinine
• Beta-blockers
• MAO inhibitors
• Bactrim (an antibiotic)
• Haloperidol

Symptoms

• Anxiety
• Shakiness
• Palpitations
• Sweating
• Nightmares
• Irritability
• Hunger

Symptoms of long-term (chronic) hypoglycemia can include ataxia (movement difficulties), convulsions, confusion, extreme tiredness (lethargy) and coma.

Exams and Tests

A blood test will show a plasma glucose level of less than 45 mg/dL.

In cases where people without diabetes have taken drugs for the condition, blood tests may show a high serum insulin level with a low serum C-peptide level. The urine may test positive for sulfonylureas.

Treatment

The patient will be given glucose. The doctor will review the person's diabetes treatment plan to help prevent future problems.

Outlook (Prognosis)

The outlook is good if the hypoglycemia is promptly detected and treated. However, long-term and repeated episodes of hypoglycemia may damage the brain and nerves.

Possible Complications

Complications of severe or prolonged hypoglycemia include neurologic damage, convulsions, and coma.

When to Contact a Medical Professional

Call your health care provider if you have symptoms of hypoglycemia and be sure to mention any medications you believe may be associated with the condition.

Prevention

For persons with diabetes, strict control of blood sugar is important. This can be done with home blood sugar testing, exercise, and proper diet. You should discuss any planned changes of diet, exercise, travel, weight, or routine with your health care provider. Your treatment plan may be adjusted in advance to prevent hypoglycemia.

Guettier JM. Hypoglycemia. Endocrinol Metab Clin North Am. Dec 2006; 35(4): 753-66, viii-ix.

Goldman L, Ausiello D. Cecil Textbook of Medicine, 22nd ed. Philadelphia, Pa: WB Saunders; 2004:1444-1445.