Is diazoxide a vasodilator?

Key Points

• The intravenous (IV) form of diazoxide (brand example: Hyperstat) is classified as an arterial vasodilator and is used to lower blood pressure in a hypertensive (high blood pressure) emergency. Both the generic IV diazoxide and the brand Hyperstat are no longer available on the U.S. market.
• The oral form of diazoxide (for example: Proglycem) is classified as a non-diuretic benzothiadiazine derivative and is used to treat low blood sugar (hypoglycemia). It is available by prescription.
• The effects to lower blood pressure are not marked with the oral diazoxide preparations used to treat low blood sugar. However, high blood sugar can occur in the majority of patients treated with IV diazoxide, but usually requires treatment only in patients with diabetes. It will respond to the usual management, including insulin.

What is oral diazoxide?

The oral form of diazoxide (brand example: Proglycem) is used to treat low blood sugar (hypoglycemia) caused by certain cancers or other conditions that can make the pancreas release too much insulin. Oral diazoxide is for use in adults, children, infants, and newborns. You should not take oral diazoxide to treat occasional low blood sugar caused by diet.

Diazoxide raises blood sugar by slowing the release of insulin from the pancreas. The effect on lowering blood sugar begins within one hour and generally lasts no more than 8 hours in the presence of normal kidney function.

The most frequent and serious side effect with oral diazoxide is sodium (salt) and fluid retention and may result in congestive heart failure (CHF) in patients with heart problems. Using diuretic therapy can be helpful for this side effect.

Other frequently reported side effects of diazoxide include:

• Nausea
• Vomiting
• Lack of appetite
• Diarrhea
• Change in taste
• Loss of strength and energy

Related questions

• Should you use a diuretic with diazoxide?
• How does diazoxide (Proglycem) cause hyperglycemia?
• How does diazoxide slow insulin?

How is oral diazoxide given?

Oral diazoxide is given as an oral suspension; the capsule form is no longer available.

Dosages are individualized and should be adjusted based on blood glucose needs. Doses are based on weight and divided into two or three equal doses every 8 or 12 hours. Special care should be taken to assure an accurate dose in infants and young children.

Patients should be under close observation by a health care provider. The clinical response and blood sugar (glucose) levels should be monitored closely until the patient has stabilized, usually several days.

If administration of oral diazoxide (brand example: Proglycem) is not effective after 2 to 3 weeks, the medicine should be discontinued.

Bottom Line

• The intravenous formulation of diazoxide (brand example: Hyperstat) is classified as a vasodilator, and is used to lower blood pressure in a hypertensive (high blood pressure) emergency. This product is no longer available in the U.S.
• The oral suspension formulation of diazoxide (brand example: Proglycem) is used to lower blood sugar levels caused by certain conditions that make the pancreas release too much insulin, such as cancer.
• The effects to lower blood pressure are not marked with the oral diazoxide preparations used to treat low blood sugar.

This is not all the information you need to know about oral or IV diazoxide for safe and effective use. Review the full diazoxide product information here, and discuss this information with your doctor or other health care provider.