Generic and Brand Names
- diazoxide (Proglycem, Hyperstat)
- glucagon (GlucaGen)
Therapeutic Action
Raise blood glucose by cutting insulin release and speeding glycogen breakdown in the liver, which dumps glucose into circulation. Glucagon raises cyclic AMP to stimulate hepatic glycogenolysis and gluconeogenesis; because it draws down stored hepatic glycogen, the patient needs a longer-acting carbohydrate by mouth as soon as they can swallow safely (Glucagon, StatPearls). Diazoxide works from the opposite direction, opening ATP-sensitive potassium channels on the pancreatic beta cell to inhibit insulin secretion, and it is the only agent the FDA has approved for hyperinsulinism (Diazoxide, CHOP).
Indications
Diazoxide treats hypoglycemia orally; the IV form is used for severe hypertension. Glucagon reverses severe hypoglycemic reactions.
Pharmacokinetics
Here are the characteristic interactions of glucose-elevating agents and the body in terms of absorption, distribution, metabolism, and excretion:
| Route | Onset | Peak | Duration |
|---|---|---|---|
| IV | 1 min | 15 min | 9-20 min |
| Half-life (T1/2) | Metabolism | Excretion |
|---|---|---|
| 3-10 min | Liver | Bile, urine |
Contraindications and Cautions
Diazoxide is contraindicated with allergy to sulfonamides or thiazides. Both drugs cross into pregnancy and lactation with risk: diazoxide carries fetal and neonatal adverse effects, and glucagon has no adequate pregnancy studies, so use it only when maternal benefit outweighs fetal risk. Use caution in renal or hepatic dysfunction and cardiovascular disease.
Adverse Effects
Glucagon causes GI upset, nausea, and vomiting. Diazoxide relaxes arteriolar smooth muscle, so expect vascular effects: hypotension, headache, cerebral ischemia, weakness, heart failure, and arrhythmias.
Interactions
Diazoxide with thiazide diuretics raises toxicity risk, since the two are structurally the same. Glucagon increases the effect of oral anticoagulants.
Nursing Considerations
Assessment
Screen for the contraindications and cautions: allergy history, renal and hepatic dysfunction, pregnancy. Get a baseline physical, orientation, reflexes, pulse, blood pressure, and adventitious and abdominal sounds, since altered glucose and these drugs both change them. Monitor blood glucose as ordered, plus urinalysis for glucosuria, serum glucose for response, and renal and liver function to catch the need for dose adjustment or toxicity.
Nursing Diagnoses
- Risk for unstable blood glucose related to ineffective dosing of the drug
- Imbalanced nutrition: more than body requirements related to metabolic effects
Implementation
Keep insulin on standby during emergency use; an overdose can swing the patient into severe hyperglycemia. For diazoxide, track blood pressure, heart rhythm and output, and weight to head off serious cardiovascular reactions. Monitor nutritional status and arrange a consult as needed, provide comfort measures, and teach the patient the drug effects and warning signs to report.
Evaluation
Look for stable blood glucose, watch for hyperglycemia and GI distress, and confirm the patient can name the drug, its indication, and the adverse effects to watch for. Monitor compliance.
Frequently Asked Questions
When do you reach for glucagon instead of oral sugar? Glucagon is for severe hypoglycemia when the patient cannot safely take carbohydrate by mouth, such as someone who is unconscious, seizing, or unable to protect their airway. If they can swallow, oral glucose is faster and simpler (Glucagon, StatPearls).
Why give a snack after the patient wakes up from glucagon? Glucagon works by emptying the liver's glycogen stores, so the effect is temporary and glucose can fall again. Once the patient is alert and can swallow, give a longer-acting carbohydrate to refill those stores and prevent a rebound low (Glucagon, StatPearls).
How is diazoxide different from glucagon? Glucagon is a fast emergency rescue that pushes stored glucose out of the liver. Diazoxide is an oral drug that prevents lows at the source by shutting down insulin release from the pancreas, and it is the only FDA-approved treatment for hyperinsulinism (Diazoxide, CHOP).
Why does diazoxide need a sulfa allergy check? Diazoxide is structurally related to the thiazide and sulfonamide drugs, so it is contraindicated in patients with an allergy to sulfonamides or thiazides. Confirm the allergy history before giving it.
What is the main safety risk with IV diazoxide? It relaxes arteriolar smooth muscle, so it can drop blood pressure sharply and trigger headache, fluid retention, and arrhythmias. Track blood pressure, heart rhythm, weight, and intake and output closely.
Can these drugs overshoot? Yes. Keep insulin on standby during emergency use, since an overcorrection can swing the patient into hyperglycemia. Recheck serum glucose after treating and titrate to a safe range rather than a high one.