The fastest way to raise your blood sugar is to eat 15 grams of fast-acting carbohydrates, wait 15 minutes, and recheck. Blood sugar below 70 mg/dL is considered low, and most episodes can be resolved at home within minutes using simple foods you likely already have in your kitchen.
Recognizing Low Blood Sugar
Low blood sugar, or hypoglycemia, starts producing noticeable symptoms as levels drop below 70 mg/dL. Early signs include a fast heartbeat, shaking, sweating, sudden hunger, dizziness, and feeling anxious or irritable. These symptoms are your body’s alarm system, triggered by stress hormones rushing in to signal that your brain needs fuel.
If levels keep falling below 54 mg/dL, symptoms become more serious: difficulty walking, blurred vision, confusion, strange behavior, and seizures. At this stage, you may not be able to treat yourself and will need help from someone nearby. Severe hypoglycemia can cause you to pass out.
The 15-15 Rule
The standard approach recommended by the CDC is called the 15-15 rule. Eat or drink 15 grams of fast-acting carbohydrates, then wait 15 minutes and check your blood sugar again. 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 sugars that hit your bloodstream quickly, not foods with fat, protein, or fiber that slow digestion. Good options for roughly 15 grams of fast-acting carbs include:
- Glucose tablets: 3 to 4 tablets (check the label, as brands vary)
- Fruit juice: about two-thirds of a cup (150 ml)
- Regular soda: half a can (not diet)
- Honey: 1 tablespoon
- Hard candies: 4 to 5 pieces (like Lifesavers)
- Sugar: 1 tablespoon dissolved in water
Glucose tablets are the most precise option since they’re pre-measured and portable. Juice and regular soda work well because they’re liquid, which speeds absorption. Avoid chocolate, cookies, or peanut butter crackers as your first treatment. The fat in these foods delays sugar absorption when speed matters most.
Preventing Another Drop
Fast-acting carbs raise your blood sugar quickly, but they also burn off quickly. If your next meal is more than an hour away, follow up with a small snack that includes both complex carbohydrates and protein. A piece of toast with peanut butter, cheese and crackers, or a handful of nuts with a piece of fruit can help sustain your levels and prevent a second dip.
This follow-up step matters because the 15 grams of sugar you initially consumed will be used up fast. Without something more substantial behind it, your blood sugar can slide right back down, especially if the original cause (like too much insulin or a missed meal) is still in play.
When Someone Else Needs to Step In
Severe hypoglycemia means a person can’t treat themselves. They may be confused, unresponsive, or having a seizure. Never try to put food or liquid in the mouth of someone who is unconscious or unable to swallow safely, as this creates a choking risk.
This is where emergency glucagon comes in. Glucagon is a hormone that signals the liver to release stored sugar into the bloodstream. It’s available in two main forms: a nasal powder that’s sprayed into the nose and a traditional injectable kit. The nasal version is dramatically easier to use in an emergency. In one study, about 91% of both trained and untrained people successfully administered the nasal spray, compared to just 8% who managed the injectable version correctly. The injectable kit requires mixing a powder with liquid before injection, and under the stress of an emergency, most people couldn’t complete the steps. If you’re prescribed glucagon, the nasal spray is the more practical choice, especially for family members or coworkers who may need to use it without prior training.
Administration takes under a minute with the nasal device. The person should be placed on their side in case of vomiting, and emergency services should still be called.
Why Overtreating Backfires
When your blood sugar is crashing and you feel terrible, the instinct is to eat everything in sight. This is one of the most common mistakes, and it leads to a predictable problem: your blood sugar rockets too high afterward.
Part of this is simply too many carbs at once. But your body also contributes to the overshoot. When blood sugar drops dangerously low, your body releases a cascade of hormones, including glucagon, adrenaline, cortisol, and growth hormone, all working to push sugar back into your bloodstream. If you’ve also eaten a large amount of food, those hormones stack on top of the incoming carbs, and you end up with blood sugar well above your target range. This pattern of low followed by high can make overall blood sugar control harder to manage over time.
Stick to the 15-15 rule even when it feels painfully slow. Fifteen grams, fifteen minutes, recheck. It prevents the rollercoaster.
Common Triggers to Watch For
Knowing what causes blood sugar to drop helps you prevent episodes in the first place. The most common triggers include skipping or delaying meals, taking too much insulin or certain diabetes medications, and exercising more intensely than usual without adjusting food intake.
Alcohol deserves special attention because its effects are delayed and often unexpected. When your liver is processing alcohol, its ability to produce new glucose drops by up to 45%. Your liver normally acts as a backup fuel supply, steadily releasing sugar between meals. Alcohol disrupts that process. Once your liver’s stored sugar (glycogen) runs out, it can’t manufacture more efficiently, and blood sugar can drop 8 to 10 hours after drinking. This means a few drinks in the evening can cause low blood sugar the following morning. Eating a meal with your drinks and checking your blood sugar before bed reduces this risk.
Exercise can cause a similar delayed effect. Physical activity makes your muscles more sensitive to insulin and uses up stored glucose. Blood sugar can continue to fall for hours after a workout, particularly after prolonged or intense sessions. Having a carb-containing snack before or after exercise, and monitoring your levels, helps you stay ahead of it.
Keeping Supplies Within Reach
Low blood sugar episodes don’t wait for convenient moments. Keep fast-acting carbs in multiple locations: your bag, your car, your desk at work, and your bedside table. Glucose tablets are ideal for this because they’re shelf-stable, portable, and pre-dosed. A small juice box works too.
If you use insulin or medications that can cause lows, wearing a medical ID bracelet or carrying a card in your wallet helps others know what’s happening if you can’t communicate. And if you’ve been prescribed a glucagon device, make sure at least one person in your daily life knows where it is and how to use it. A tool that stays in a drawer during an emergency doesn’t help anyone.