To correct low blood sugar, eat 15 grams of fast-acting carbohydrates, wait 15 minutes, then recheck your blood sugar. This approach, known as the 15-15 rule, is the standard recommended by the CDC and the American Diabetes Association. Pure glucose works fastest, but juice, regular soda, or hard candy will also raise your levels. The key is knowing exactly what to reach for, how much to take, and what to do next.
Recognizing the Warning Signs
Low blood sugar typically announces itself in two waves. The early signs come from your body’s stress response: sweating, a racing heart, shaking hands, anxiety, and sudden hunger. These symptoms act as an alarm system, giving you time to act before things get worse.
If blood sugar keeps dropping, the brain starts running short on fuel. That second wave looks different: confusion, difficulty concentrating, irritability, slurred speech, and trouble with coordination. At this stage, thinking clearly enough to help yourself becomes harder, which is why acting on the early symptoms matters so much. Some people lose consciousness entirely, and at that point someone else needs to step in.
Blood Sugar Levels That Need Correction
Not every dip feels the same, and the numbers help explain why. Blood sugar below 70 mg/dL is considered low and calls for treatment. Between 54 and 69 mg/dL, you’re in mild territory. Most people feel the classic warning signs here and can treat themselves without difficulty.
Below 54 mg/dL is moderate hypoglycemia. Symptoms are more intense, and your ability to think clearly may already be slipping. Below that threshold, or anytime someone can’t function or needs help from another person, the situation is classified as severe. Severe episodes require a different response entirely, which we’ll cover below.
The 15-15 Rule Step by Step
When your blood sugar drops below 70 mg/dL and you’re alert enough to eat or drink, here’s the process:
- Eat 15 grams of fast-acting carbohydrates. Good options include 3 to 4 glucose tablets, 4 to 6 ounces of fruit juice or regular soda (not diet), or 6 Life Savers candies.
- Wait 15 minutes. Your body needs time to absorb the sugar and move it into your bloodstream.
- Recheck your blood sugar. If it’s still below 70 mg/dL, repeat the process with another 15 grams of carbohydrates.
Pure glucose, whether as tablets or gel, is the preferred first treatment. It enters the bloodstream faster than other foods because your body doesn’t need to break it down further. The American Diabetes Association specifically advises against using foods high in fat or protein for the initial correction. Fat slows down sugar absorption, which is the opposite of what you need in the moment. A peanut butter sandwich might sound like a reasonable choice, but it won’t raise your levels fast enough. Protein can actually trigger additional insulin release, making it a poor choice for correcting a low.
If you use an automated insulin delivery system (an insulin pump paired with a continuous glucose monitor), the recommendation is slightly different. These systems reduce insulin delivery automatically when your sugar drops, so you typically only need 5 to 10 grams of carbohydrates unless the low is related to exercise or you significantly overestimated carbs at a meal.
What to Do After Your Levels Stabilize
Once your blood sugar is back above 70 mg/dL, eat a small snack or your next meal within the hour to keep levels steady. A combination of complex carbohydrates and protein works well here, like whole-grain crackers with cheese or a handful of nuts with a piece of fruit. This follow-up step prevents your blood sugar from crashing again once the fast-acting sugar wears off.
Resist the urge to overeat. When you’re shaky and hungry, it’s natural to want to consume everything in the kitchen, but overdoing it can send blood sugar soaring in the other direction. Stick to the 15-gram increments and let the recheck guide you.
When Someone Else Needs to Help
Severe hypoglycemia means the person can’t treat themselves. They may be confused, unresponsive, or unconscious. If someone near you is in this state, do not put food or liquid in their mouth. The choking risk is serious.
Glucagon is the go-to emergency treatment. It’s a hormone that signals the liver to release stored sugar into the bloodstream, and it works even when the person is unconscious. Glucagon comes in two main forms: a nasal spray and an injectable kit. The nasal version is dramatically easier to use. In one study comparing the two, untrained bystanders successfully administered nasal glucagon about 90% of the time, compared to less than 8% for the injectable version. The injectable form requires mixing a powder with liquid before injection, and under the stress of an emergency, most people can’t get through those steps correctly. If you or someone in your household is at risk for severe lows, a nasal glucagon device stored somewhere accessible (bedside drawer, backpack, desk) is a practical choice. Make sure at least one other person, whether a partner, coworker, or family member, knows where it is and how to use it. If no glucagon is available, call 911.
Handling Low Blood Sugar at Night
Nocturnal hypoglycemia is particularly risky because you can’t feel the warning signs while asleep. You might wake up with a headache, damp sheets from sweating, or a feeling of exhaustion, all clues that your blood sugar dropped overnight. Some people sleep through the entire episode without waking.
A continuous glucose monitor with low-glucose alerts is the most reliable safety net. These devices check blood sugar every five minutes and sound an alarm if levels fall too low, waking you so you can treat the drop. If you experience frequent overnight lows, setting a manual alarm for the early morning hours to check your blood sugar can also help identify patterns.
If you find someone in bed who won’t wake up and you suspect low blood sugar, do not try to give them food or drink. Use glucagon if it’s available. If not, call emergency services immediately.
When You’ve Lost Your Warning Signals
Some people with diabetes, especially those who’ve had the condition for many years or who experience frequent lows, stop feeling the early symptoms. This is called hypoglycemia unawareness. Without the sweating, shaking, and racing heart, blood sugar can drop to dangerous levels before the person realizes anything is wrong.
The good news is that this condition can be reversed. Studies have shown that strictly avoiding hypoglycemia for a period of time can reset the body’s alarm system, allowing symptoms to return. This usually means keeping blood sugar targets slightly higher for a while and monitoring more frequently. A continuous glucose monitor is especially valuable here, since it fills in for the missing physical warnings.
People with hypoglycemia unawareness should always check blood sugar before driving and keep fast-acting carbohydrates within reach. Alcohol and heavy exercise both increase the risk of lows, so adjusting food intake and, if applicable, insulin doses on active days or days involving alcohol is important.
Low Blood Sugar Without Diabetes
Not everyone who experiences low blood sugar has diabetes. Reactive hypoglycemia causes blood sugar to drop within a few hours after eating, typically triggered by the body overproducing insulin in response to a carbohydrate-heavy meal. If this describes your experience, the treatment approach shifts from correction to prevention.
Dietary changes are the primary strategy. Eating balanced meals that include fiber-rich foods like whole grains, vegetables, and fruits helps slow the absorption of sugar and prevents the insulin spike that causes the crash. Avoiding sugary foods and refined carbohydrates on an empty stomach makes a noticeable difference for most people. Eating smaller, more frequent meals rather than a few large ones also helps keep blood sugar steady throughout the day. Reactive hypoglycemia usually doesn’t require medication, but if episodes are frequent or severe, a medical evaluation can rule out other underlying causes.