Urgent & emergency
Diabetic Emergency: Low Blood Sugar and Passing Out
If a person with diabetes is unconscious or cannot be woken, call 911 immediately and do not put anything in their mouth — they can choke. If a glucagon kit is available, use it right away while calling 911. Severe hypoglycemia is defined as a blood glucose episode requiring the assistance of another person [1] and is a medical emergency once someone cannot help themselves.
How do you know if this is a low blood sugar emergency?
Low blood sugar (hypoglycemia) has two stages that call for different responses.
Mild to moderate: The person is conscious and can swallow. Signs include shakiness, sweating, pale skin, confusion, irritability, and a racing heart. At this stage, fast-acting sugar can reverse the episode.
Severe: The person cannot follow instructions, is extremely confused or combative, is having a seizure, or is unconscious. At this stage, giving sugar by mouth is dangerous — they could choke. Emergency services are needed immediately.
The American Diabetes Association defines severe hypoglycemia as an episode requiring the assistance of another person — regardless of the blood glucose level recorded 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool. Hypoglycemia unawareness is a real concern: people with long-standing diabetes can lose the ability to feel early warning symptoms and may go from appearing fine to unresponsive quickly, making bystander awareness essential 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool2Ref 2Centers for Disease Control and Prevention (2024).Low Blood Sugar (Hypoglycemia).Defines hypoglycemia as blood glucose below 70 mg/dL and severe hypoglycemia below 54 mg/dL; describes hypoglycemia unawareness; explains severe symptoms including loss of consciousness; glucagon as emergency treatment for severe episodes.
What to do — step by step
If they are conscious and able to swallow: 1. Give a fast-acting sugar source — 4 ounces of juice or regular soda, glucose tablets, or a few pieces of candy. 2. Stay with them. Reassess in 15 minutes. 3. If they do not improve or get worse, call 911.
If they are unconscious, seizing, or cannot swallow: 1. Call 911 immediately. 2. Do not put anything in their mouth. 3. Place them on their side if possible to protect the airway. 4. If a glucagon kit (injectable or nasal spray) is nearby and you know how to use it, give it while someone else calls 911. 5. Stay with them until help arrives.
Glucagon is a prescription hormone that signals the liver to release stored glucose. It can reverse severe hypoglycemia within minutes 2Ref 2Centers for Disease Control and Prevention (2024).Low Blood Sugar (Hypoglycemia).Defines hypoglycemia as blood glucose below 70 mg/dL and severe hypoglycemia below 54 mg/dL; describes hypoglycemia unawareness; explains severe symptoms including loss of consciousness; glucagon as emergency treatment for severe episodes. According to the American Diabetes Association, anyone using insulin should have a glucagon kit at home and household members should know how to use it 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool.
What is hypoglycemia unawareness and why does it matter?
Hypoglycemia unawareness develops in some people with type 1 or long-standing type 2 diabetes when the body's counter-regulatory hormone response becomes blunted — the usual warning signals (shakiness, sweating, heart pounding) no longer fire reliably 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool. Studies suggest that hypoglycemia unawareness affects approximately 25% of people with type 1 diabetes and a smaller but meaningful proportion of people with type 2 diabetes who use insulin 2Ref 2Centers for Disease Control and Prevention (2024).Low Blood Sugar (Hypoglycemia).Defines hypoglycemia as blood glucose below 70 mg/dL and severe hypoglycemia below 54 mg/dL; describes hypoglycemia unawareness; explains severe symptoms including loss of consciousness; glucagon as emergency treatment for severe episodes.
For people with hypoglycemia unawareness, continuous glucose monitoring (CGM) with low-glucose alerts can provide a technological substitute for the body's missing warning system — an approach supported by clinical guidelines 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool.
Why alcohol makes low blood sugar more dangerous
Alcohol suppresses the liver's ability to release stored glucose and can mask the usual warning signs of low blood sugar — sweating, shakiness, and confusion. Someone who has been drinking may slip from mild hypoglycemia to unconsciousness more quickly and with less warning. Emergency services are needed even if alcohol seems like an obvious explanation for altered consciousness.
After the emergency: what the care team needs to review
Even if someone recovers at home after sugar or glucagon, a severe low blood sugar episode warrants a clinician review. It can signal that the insulin dose, meal timing, activity level, or monitoring routine needs adjustment. According to the American Diabetes Association Standards of Care, recurring severe hypoglycemia is dangerous and avoidable — but managing it requires a clinical review, not just waiting out future episodes 1Ref 1American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool.
Bring these details to the follow-up visit: - The blood glucose reading at the time of the episode (if checked) - Names and doses of diabetes medications - Time of last meal and last insulin dose - Whether glucagon was given and when
Common questions
What blood sugar level counts as low?
The American Diabetes Association defines hypoglycemia as a blood glucose level below 70 mg/dL [1]. Severe hypoglycemia — the kind that requires outside help — is generally any level where the person cannot treat themselves, or a blood glucose below 54 mg/dL [1]. Work with your care team to set personalized thresholds.
Can low blood sugar look like a stroke?
Yes — severe hypoglycemia can cause sudden confusion, slurred speech, and difficulty walking that closely mimics a stroke. This is why blood glucose is checked immediately in the ER for anyone with sudden neurological symptoms. If you are unsure, call 911.
Should everyone with diabetes have a glucagon kit?
Anyone who uses insulin or medications that can cause low blood sugar should discuss a glucagon prescription with their care team [1]. Glucagon kits — available in injectable and nasal spray forms — can reverse a severe episode when the person cannot safely eat or drink [2].
Is it safe to give juice to someone who is unconscious?
No. An unconscious person cannot protect their airway and can choke on liquids. Never give anything by mouth to someone who is unresponsive. Call 911 and use glucagon if available.
Call 911 immediately if any of these are present
- —Person is unconscious or cannot be woken
- —Seizure is occurring
- —Person is too confused to swallow safely
- —No improvement after giving fast-acting sugar and waiting 15 minutes
- —Breathing is abnormal or slow
Call 911 immediately if the person is unconscious, seizing, or cannot swallow safely. This is a medical emergency. Do not leave the person alone.
This article provides general emergency guidance only. It is not a personalized medical plan. Call 911 for any unconscious or seizing person. Always work with a clinician to manage diabetes and prepare for emergencies.
References
- 1.American Diabetes Association Professional Practice Committee (2024). 6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024. Diabetes Care. doi:10.2337/dc24-S006 ✓Defines severe hypoglycemia as requiring assistance of another person; thresholds of <70 mg/dL and <54 mg/dL; glucagon prescription for all insulin users; clinical review after severe episodes; hypoglycemia unawareness and CGM as a management tool
- 2.Centers for Disease Control and Prevention (2024). Low Blood Sugar (Hypoglycemia). CDC Diabetes. link ✓Defines hypoglycemia as blood glucose below 70 mg/dL and severe hypoglycemia below 54 mg/dL; describes hypoglycemia unawareness; explains severe symptoms including loss of consciousness; glucagon as emergency treatment for severe episodes
- 3.MedlinePlus — National Library of Medicine (2023). Low Blood Sugar (Hypoglycemia). MedlinePlus. link ✓Consumer-facing overview of hypoglycemia signs, symptoms, emergency steps, and when to call 911; explains the 15-minute rule and the role of glucagon in emergency treatment
3 sources, numbered by first appearance. General health information, not medical advice — synthetic demonstration content.