When blood sugar drops below 70 mg/dL, eating 15 grams of fast-acting carbohydrates is the most effective first step. The specific approach depends on how low the reading is and whether the person is conscious, but acting quickly is what matters most. Here’s what to do, what to use, and how to handle more serious drops.
Recognize the Symptoms First
Low blood sugar triggers two waves of symptoms. The first wave comes from your body’s stress response: sweating, shakiness, a racing heart, anxiety, and sudden intense hunger. These are your early warning signs, and they’re your best window to act.
If blood sugar keeps falling, a second set of symptoms appears as the brain starts running short on fuel. These include weakness, dizziness, difficulty concentrating, confusion, blurred vision, and behavior changes that can look like intoxication. In extreme cases, this can progress to seizures or loss of consciousness. Recognizing these signs in yourself or someone else is the critical first step, because treatment changes depending on severity.
The 15-15 Rule for Mild to Moderate Lows
For anyone who is conscious and able to swallow, the standard treatment is called the 15-15 rule: eat or drink 15 grams of fast-acting carbohydrates, wait 15 minutes, then recheck your blood sugar. If it’s still below 70 mg/dL, repeat the process. Keep going until your levels return to your target range.
The key word here is “fast-acting.” You want simple sugar that hits your bloodstream quickly, not foods with fat or protein that slow digestion. Good options for roughly 15 grams of carbohydrates include:
- Glucose tablets: 4 to 5 tablets (4 grams each), the most precise option
- Fruit juice: about two-thirds of a cup (150 mL)
- Regular soda: about half a can (not diet)
- Honey: 1 tablespoon
- Hard candies: a small handful, depending on the brand
Glucose tablets are the preferred choice because they’re premeasured, portable, and contain pure glucose. Juice and soda work well too, but avoid chocolate, peanut butter, or ice cream as your first treatment. The fat in those foods delays sugar absorption right when you need it fastest.
Once your blood sugar is back in range, eat a balanced snack or small meal that includes both protein and carbohydrates. This helps stabilize your levels and prevents another drop. Young children, especially infants and toddlers, typically need less than 15 grams per dose, so parents should work with their child’s doctor to determine the right amount.
What to Do for a Severe Low
A severe episode, classified as Level 3 hypoglycemia, is any event where the person needs help from someone else. This includes confusion so significant they can’t treat themselves, seizures, or unconsciousness. Never try to put food or liquid into the mouth of someone who is unconscious or unable to swallow safely. They could choke.
Instead, place the person on their side in a recovery position to keep their airway clear in case they vomit. Call emergency services, and stay with them until help arrives.
If you have glucagon available and know how to use it, this is exactly the situation it’s designed for. Glucagon is a hormone that signals the liver to release stored sugar into the bloodstream. It now comes in three forms:
- Nasal spray: A needle-free powder sprayed into one nostril. It’s absorbed through the nasal lining, works quickly, and requires just one step, making it the easiest option for untrained caregivers.
- Pre-mixed pen: Works like an EpiPen. Remove the cap, inject into the upper arm, thigh, or lower stomach at a 90-degree angle. No mixing required.
- Powder-and-syringe kit: Requires mixing a powder with a liquid before injecting into the thigh or arm muscle. This older format takes more steps and some practice to use under pressure.
Anyone who takes insulin should have a glucagon prescription and make sure the people around them, family, coworkers, close friends, know where it’s kept and how to use it.
Understanding the Three Levels
The American Diabetes Association classifies hypoglycemia into three levels, and knowing the difference helps you gauge urgency. Level 1 is a blood sugar reading between 54 and 69 mg/dL. You’ll likely feel symptoms, and the 15-15 rule is the right response. Level 2 is anything below 54 mg/dL, the point where the brain starts losing adequate fuel. This requires immediate action and carries more risk. Level 3 is defined not by a number but by the need for someone else’s help, regardless of what the meter reads.
If you experience repeated Level 2 or Level 3 episodes, that’s a signal to revisit your treatment plan. Medication doses, insulin timing, or even switching to a different class of diabetes medication may need to change.
Common Causes to Watch For
For people with diabetes, the most frequent triggers are taking too much insulin, delaying or skipping meals, exercising more than usual without adjusting food or medication, and drinking alcohol on an empty stomach. Alcohol is particularly tricky because it blocks the liver from releasing stored glucose, so a drink without food can lead to a delayed drop hours later.
Low blood sugar also happens in people without diabetes, though less commonly. Reactive hypoglycemia causes a blood sugar dip a few hours after eating, especially in people who’ve had stomach surgery like gastric bypass. Severe liver disease, kidney disease, advanced heart disease, and certain medications (including some used for malaria) can also cause it. If you’re experiencing repeated lows without a clear explanation, that pattern is worth investigating.
Preventing Lows Overnight
Nocturnal hypoglycemia is one of the more dangerous patterns because you can’t feel symptoms while you’re asleep. If you take insulin or sulfonylureas, a bedtime snack that combines carbohydrates with protein or fat can help keep blood sugar stable through the night. Something like crackers with cheese or a small bowl of cereal with milk gives you both quick and slow-release fuel.
If you find yourself needing a bedtime snack regularly to avoid overnight lows, your medication dose may need adjustment rather than relying on extra food as a nightly fix.
When You Stop Feeling the Warning Signs
Some people, particularly those who have had diabetes for many years or who experience frequent lows, gradually lose the ability to feel early symptoms like shakiness and sweating. This condition, called hypoglycemia unawareness, is dangerous because the first sign of a low may be confusion or collapse rather than a gentle warning.
The encouraging news is that this can often be partially reversed. Carefully avoiding all hypoglycemic episodes for a period of weeks can help retrain the body’s alarm system. Continuous glucose monitors (CGMs) are especially valuable here because they check glucose levels every five minutes and alert you when you’re dropping, replacing the internal warning system your body has stopped providing. Sensor-augmented insulin pumps take this further by automatically suspending insulin delivery when a low is detected or predicted, reducing both the frequency and severity of episodes.
Structured education programs that teach people to better detect, treat, and prevent lows have also shown real results in restoring awareness and reducing fear of hypoglycemia. For the most severe, treatment-resistant cases, pancreas or islet cell transplantation can restore the body’s natural ability to regulate insulin and glucagon almost immediately.