If a person with diabetes passes out, call 911 immediately and do not put anything in their mouth. Loss of consciousness in someone with diabetes is most often caused by severely low blood sugar, typically below 54 mg/dL. Acting quickly and calmly in the first few minutes can prevent serious harm while you wait for emergency help.
Call 911, Then Protect Their Airway
The moment someone with diabetes loses consciousness, call 911. Tell the operator the person has diabetes if you know that. While you’re on the phone or waiting for help, your most important job is keeping their airway clear.
Roll the person onto their side into what’s called the recovery position. This lets any fluid, saliva, or vomit drain from their mouth and nose instead of being breathed into the lungs. Tilt the head up slightly so the airway stays open, and rest their hand under their cheek to help hold this position. Do not move them this way if you suspect a back or neck injury from their fall.
Do not give them food, juice, candy, or water. An unconscious person cannot swallow safely, and anything placed in their mouth can block their airway or be inhaled into the lungs. This is one of the most common mistakes bystanders make, and it’s dangerous.
How to Use Emergency Glucagon
Many people with diabetes carry an emergency glucagon kit, which raises blood sugar rapidly. If you can find one in their bag, car, or on their person, you can administer it even without medical training. There are two main types.
Nasal spray: This is the simplest option. It delivers a dry powder of glucagon into one nostril. Insert the tip into a nostril, press the plunger, and you’re done. The person does not need to inhale or be awake for it to work. The medication absorbs passively through the lining of the nose. Lay the person on their side, with the treated nostril facing up.
Injectable kit: This type requires you to mix a powder with a liquid before injecting it into a large muscle, typically the upper arm. The kit includes instructions, and the steps take about a minute. Inject into the arm opposite the side the person is lying on.
After receiving glucagon, a person should regain consciousness within 15 minutes. If they don’t wake up in that time, a second dose can be given. Even if they do wake up, emergency medical care is still necessary. Glucagon buys time; it does not resolve the underlying problem.
What Happens After They Wake Up
Once the person is conscious and clearly able to swallow, give them a fast-acting source of sugar: about 4 ounces of juice or regular (not diet) soda, 3 to 4 glucose tablets, a tablespoon of sugar, or 6 to 8 hard candies. Any of these provides roughly 15 grams of carbohydrate, which is the standard amount to start raising blood sugar back toward a safe range.
If a glucose meter is available, check their blood sugar after 15 minutes. If it’s still below 70 mg/dL, repeat with another 15 grams of fast-acting carbohydrate. Keep repeating this cycle until the reading is above 70.
Once blood sugar stabilizes, the person should eat a real meal or substantial snack. The fast-acting sugar works quickly but wears off just as fast. A meal with protein, fat, and complex carbohydrates helps prevent blood sugar from crashing again in the next hour or two.
Low Blood Sugar vs. High Blood Sugar
Both dangerously low and dangerously high blood sugar can cause someone with diabetes to pass out, but they look different. Knowing which one you’re dealing with helps, though in either case the correct first step is calling 911.
Low blood sugar (hypoglycemia) tends to come on fast. The person’s skin often looks pale and feels cool and clammy. They may be sweating visibly, and their heartbeat may feel fast or irregular. Before losing consciousness, they might have seemed shaky, confused, irritable, or even appeared intoxicated.
High blood sugar (hyperglycemia) develops more gradually, often over hours or days. A key sign is a fruity or sweet odor on the person’s breath, caused by the body breaking down fat for fuel. Breathing may be unusually fast or deep, and the person may have mentioned frequent urination or extreme thirst in the hours before collapsing.
If you’re unsure which type of emergency it is, do not guess with treatment. Call 911 and keep the person in the recovery position. If glucagon is available and you suspect low blood sugar based on the signs above, using it is reasonable because raising blood sugar in someone with severe hypoglycemia can be lifesaving, while the temporary sugar increase is unlikely to cause lasting harm in someone whose sugar is already high.
Signs to Watch for Before a Collapse
Fainting from diabetes rarely happens without warning signs. If someone with diabetes starts showing any of the following, they may be heading toward a loss of consciousness:
- Confusion or disorientation that seems to come on suddenly
- Shakiness, weakness, or dizziness
- Excessive sweating unrelated to heat or exercise
- Slurred speech or difficulty walking, sometimes mistaken for intoxication
- Rapid heartbeat
- Seizure activity
If you notice these signs and the person is still conscious and able to swallow, that is the window to act with fast-acting sugar before the situation escalates. A few glucose tablets or a small glass of juice at this stage can prevent a full collapse entirely. Once someone loses consciousness, oral sugar is off the table, and you’re relying on glucagon or emergency medical services.
What to Tell the Paramedics
When emergency responders arrive, give them as much information as you can. Tell them the person has diabetes, how long they’ve been unconscious, whether they had a seizure, and whether you administered glucagon (and what type). If you know what medications the person takes or whether they recently ate, share that too. If a glucose meter reading is available, pass along the number. All of this helps paramedics choose the right treatment faster.