Warning Signs and Emergency Presentations

This guide does not replace an individualized emergency plan from your specialist. Managing an INSR-related syndrome means living with extreme metabolic swings. Most days involve navigating high and low blood sugars that, while stressful, are part of the daily routine. However, because the body’s relationship with insulin is fundamentally altered, certain situations can escalate into medical emergencies that require specialized hospital care.

When to Seek Emergency Care

An emergency is not a routine high or low blood sugar that responds to your usual home treatments. Instead, an emergency occurs when the body’s metabolic balance collapses or when symptoms become life-threatening.

Seek immediate emergency medical attention (Call 911 or your local emergency services) for:

• Altered Mental State: Confusion, extreme lethargy, inability to wake up, or acting “drunk” or bizarre.
• Loss of Consciousness or Seizures: Any fainting or seizure activity, which may be caused by profound hypoglycemia ^[1].
• Respiratory Distress: Deep, rapid, “sighing” breathing (Kussmaul breathing), which is a sign of severe acid buildup in the blood (acidosis) ^[2].
• Persistent Vomiting: Inability to keep down fluids or glucose, which quickly leads to dehydration and metabolic crisis ^[3].
• Suspected DKA: Severe abdominal pain, “fruity” smelling breath, and moderate-to-high ketones in the urine or blood ^[4]. (Note: If you take an SGLT2 inhibitor, DKA can be urgent even with normal glucose).

Emergency Hypoglycemia Rescue Protocol

Because low blood sugar can happen rapidly, every patient needs a written rescue plan. In general:

1. If awake and able to swallow: Give oral fast-acting carbohydrates (like juice or glucose tabs).
2. If unconscious, seizing, or unable to swallow: DO NOT put food or liquid in their mouth (risk of choking).
3. Use prescribed rescue medication: Administer prescribed emergency glucagon or wait for emergency services to administer IV dextrose.
4. Call 911 immediately if the person is unconscious, seizing, or fails to respond quickly to treatment.

The Danger of Refractory DKA

In Rabson-Mendenhall Syndrome (RMS) and occasionally in other severe forms, patients can develop Diabetic Ketoacidosis (DKA). While DKA is a known complication of diabetes, in INSR deficiency, it is “refractory,” meaning it does not respond to standard doses of insulin.

Because the insulin receptors are defective, the body ignores the insulin levels that would normally save a patient. In hospital settings, patients with RMS may require unusually high doses of intravenous insulin that far exceed standard guidelines, alongside intense monitoring of potassium, glucose, and acid-base balance by an ICU/metabolic team ^[2][4]. If you go to an ER, always bring an emergency letter outlining your exact diagnosis and provide your specialist’s direct phone number, as the care team will need to coordinate an individualized approach.

The Paradoxical “Crash” (Hypoglycemia)

While resistance usually implies “high” blood sugar, the most dangerous daily risk is often the “crash” into hypoglycemia (low blood sugar). This is paradoxical because it happens when insulin levels are actually at their highest ^[5].

• Postprandial Hypoglycemia: This occurs a few hours after eating. Blood sugar may spike initially after a meal and then plummet rapidly as the body’s massive overproduction of insulin finally “overpowers” the resistance ^[6][7].
• Fasting Hypoglycemia: Some patients, particularly those with Donohue Syndrome, experience dangerous drops after several hours without food because the liver cannot release sugar correctly ^[8].
• Symptoms of a “Crash”: Sweating, tremors, rapid heartbeat, extreme hunger, irritability, or sudden paleness.

Physical Signs and Overlooked Symptoms

Beyond blood sugar, INSR syndromes cause visible changes in the body. These signs are often the first clues for doctors and can vary across the spectrum:

When to Call for a Same-Day Appointment

Not every concern requires the ER, but some require a call to your specialist the same day:

• Trace or Small Ketones: Seeing “trace” or “small” ketones on a home test when blood sugar is high requires clinician advice for sick-day management. Moderate/large ketones are an emergency.
• Unexplained Spikes or Drops: Blood sugars staying outside your target range without an obvious cause like a missed dose.
• New Physical Symptoms: Rapidly worsening skin patches or sudden changes in growth or development.
• Mild Illness: A fever, cold, or minor infection can rapidly destabilize blood sugar in someone with INSR deficiency ^[14]. Do not wait 24 hours to call if you are ill; always contact your team at the first sign of illness to adjust your management plan.