To fix low blood sugar, eat or drink 15 grams of fast-acting carbohydrates, wait 15 minutes, then check your blood sugar again. Blood sugar below 70 mg/dL is considered low, and anything below 54 mg/dL is severely low and may require help from someone else. Most mild to moderate episodes can be resolved at home within minutes if you act quickly.
The 15-15 Rule
The standard approach for treating low blood sugar is called the 15-15 rule: consume 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. The goal is a controlled, steady rise rather than overcorrecting with too much sugar at once, which can send your levels swinging in the other direction.
Good sources of 15 grams of fast-acting carbs include:
- Glucose tablets: follow the package directions (usually 3 to 4 tablets)
- Fruit juice: about two-thirds of a cup (150 mL)
- Regular soda: about half a can (not diet)
- Honey or sugar: roughly 1 tablespoon
- Hard candies: check the label for carb count
The key word here is “fast-acting.” You want simple sugars that hit your bloodstream quickly. Chocolate, peanut butter cups, or ice cream are poor choices for this step because their fat content slows down how fast your body absorbs the sugar. Save those for later. Stick with something that’s mostly pure carbohydrate.
Follow Up With a Real Snack
Once your blood sugar climbs back above 70 mg/dL, you’re not done. Fast-acting carbs wear off quickly, and without a follow-up snack, your levels can drop again. The trick is pairing about 15 grams of carbohydrates with some protein, which slows digestion and keeps your blood sugar stable for longer.
Practical options include half a sandwich with meat or cheese, crackers with peanut butter, an apple with a small handful of nuts, or a few rice cakes with peanut butter. If your next full meal is less than an hour away, you can skip the snack and just eat your meal. The point is to give your body something more substantial to work with so you don’t end up in a second low.
Recognizing the Symptoms
Low blood sugar tends to announce itself with a fairly recognizable set of feelings: shakiness, sweating, a racing heartbeat, sudden hunger, dizziness, or feeling irritable and anxious for no clear reason. Some people get blurry vision or a tingling sensation around the mouth. These symptoms come on fast, often within minutes.
As blood sugar drops further, symptoms get more serious. Confusion, difficulty speaking, clumsiness, and extreme drowsiness all signal that the brain isn’t getting enough fuel. At this stage, the person may not be able to treat themselves and will need someone nearby to help. If you live with someone who takes insulin or diabetes medication, make sure they know what to look for and what to do.
When Someone Can’t Treat Themselves
Severe low blood sugar, below 54 mg/dL, can cause seizures or loss of consciousness. If someone is unresponsive, call 911 immediately. Do not try to put food or liquid in the mouth of someone who is unconscious or too confused to swallow safely, as they could choke.
This is where glucagon comes in. Glucagon is a prescription emergency treatment that signals the liver to release stored sugar into the bloodstream. It now comes in several forms that don’t require medical training to use. A nasal spray version works in one step, similar to a nasal decongestant, and can be given to someone who is unconscious. There are also pre-filled injection pens that work like an EpiPen, ready to use without any mixing. Older kits require mixing a powder with liquid before injecting, which is trickier under pressure. If someone in your household is at risk for severe lows, ask their doctor about keeping one of these on hand and practice with it before an emergency happens.
After giving glucagon, turn the person on their side. Nausea and vomiting are common as they come around, and lying on their side prevents choking.
Why Blood Sugar Drops in the First Place
For people with diabetes, the most common triggers are straightforward: too much insulin, a delayed or skipped meal, or more physical activity than usual without adjusting food intake. Alcohol can also lower blood sugar, sometimes hours after drinking, because it interferes with the liver’s ability to release glucose.
Low blood sugar in people without diabetes is less common but does happen. Reactive hypoglycemia causes a drop one to four hours after eating, particularly after high-carbohydrate meals. It’s more frequent in people who have had stomach surgery, especially gastric bypass, because food moves through the digestive system faster than normal. Certain medications can also trigger lows. Taking someone else’s diabetes medication accidentally is one obvious cause, but other drugs, like quinine used for malaria, can have the same effect. In children, low growth hormone levels can lead to hypoglycemia.
Preventing Repeat Episodes
If low blood sugar happens to you once, it will likely happen again unless you address the pattern behind it. Start by looking at timing. Did you skip a meal? Exercise harder than usual? Take medication on an empty stomach? Most episodes trace back to a mismatch between the sugar entering your bloodstream and the insulin (or medication) pulling it out.
Eating regular meals and snacks that combine carbohydrates with protein and some fat helps keep blood sugar steady throughout the day. If you take insulin, checking your levels before driving, exercise, and sleep catches lows before they become symptomatic. Keeping glucose tablets or juice boxes in your car, desk, gym bag, and nightstand means you’re never caught without a fast fix. A medical ID bracelet or card in your wallet tells first responders what’s going on if you can’t speak for yourself.
If you’re experiencing frequent lows, that’s a signal your medication dose or meal timing needs adjusting. Repeated episodes below 54 mg/dL are especially concerning because, over time, your body can stop producing warning symptoms, a condition called hypoglycemia unawareness. You go from feeling fine to being dangerously low with no shakiness or sweating in between. Tracking your episodes and sharing the pattern with your care team is the single most useful thing you can do to prevent it from getting worse.