If your blood sugar has dropped below 70 mg/dL, the fastest way to bring it back up is to eat or drink 15 grams of fast-acting carbohydrates, wait 15 minutes, and recheck. This approach, known as the 15-15 rule, is the standard recommended by the CDC and most diabetes organizations. It works within minutes and helps you avoid overcorrecting into a blood sugar spike.
The 15-15 Rule Step by Step
When you feel symptoms of low blood sugar or your meter reads below 70 mg/dL, immediately consume 15 grams of simple carbohydrates. Then wait 15 minutes and check again. If your reading is still under 70, eat another 15 grams. Repeat until your blood sugar is back in your target range.
The key is using fast-acting carbs that your body absorbs quickly. These are foods with simple sugars and little to no fat, fiber, or protein slowing them down. Good options that deliver roughly 15 grams include:
- 4 ounces (half a cup) of fruit juice
- 4 ounces of regular soda (not diet)
- 1 tablespoon of honey or sugar
- Glucose tablets (follow the package for the right number, usually 3 to 4)
- Hard candies like Lifesavers (typically 5 to 6 pieces)
Glucose tablets are the most precise option because each tablet contains a measured amount of glucose. Juice and honey work well too, but eyeball portions carefully. Chocolate, cookies, and ice cream are poor choices in the moment because their fat content slows absorption, meaning your blood sugar takes longer to recover.
Why You Shouldn’t Overdo It
When your blood sugar drops, the urge to eat everything in sight is strong. That’s partly biological. Your body releases stress hormones like adrenaline and glucagon during a low, which ramp up hunger and anxiety. But eating far more than 15 grams of carbs at once often sends blood sugar rocketing in the other direction.
This rebound effect can leave you with a reading well above your target range a few hours later. Your body’s own counterregulatory response is already working to push glucose out of your liver and into your bloodstream. Pile a large amount of carbohydrates on top of that hormonal response, and you get a spike that’s hard to bring back down. The 15-15 rule exists specifically to prevent this cycle of low-then-high that can make blood sugar management feel chaotic.
Recognizing the Symptoms
Low blood sugar typically announces itself with shakiness, sweating, a fast heartbeat, irritability, or sudden hunger. You might feel lightheaded, confused, or notice your vision blurring. These symptoms can come on quickly, sometimes within minutes.
One complication worth knowing about: if you experience frequent lows, your body can stop sending these warning signals altogether. This is called hypoglycemia unawareness, and it means your blood sugar can drop dangerously low without the usual red flags. People with hypoglycemia unawareness often need adjusted blood sugar targets and more frequent monitoring to stay safe.
What Causes Blood Sugar to Drop
The most common triggers are straightforward. Skipping or delaying a meal, being more physically active than usual, or drinking alcohol on an empty stomach can all pull your blood sugar down. For people with diabetes, taking too much insulin or certain oral medications is the leading cause.
Several types of diabetes medications increase the risk of lows, particularly sulfonylureas and glinides, which stimulate the pancreas to release more insulin regardless of what you’ve eaten. Even some non-diabetes drugs can contribute. Certain antibiotics, heart rhythm medications, beta-blockers, and anti-inflammatory pain relievers have been linked to unexpected blood sugar drops. If you’re experiencing lows and aren’t sure why, your medication list is worth reviewing.
What to Do After Your Blood Sugar Recovers
Once your reading is back above 70 mg/dL, eat a small meal or snack that includes protein, fat, and complex carbohydrates. This combination digests more slowly and helps stabilize your blood sugar so it doesn’t dip again 30 to 60 minutes later. A handful of crackers with peanut butter, a slice of cheese with whole grain bread, or half a sandwich are all solid choices.
If your next meal is more than an hour away, this follow-up snack is especially important. The fast-acting carbs you used to treat the low are already being metabolized, and without something more substantial, you risk sliding back down.
Preventing Lows Overnight
Nighttime lows are particularly concerning because you’re asleep and less likely to notice symptoms. Research has found that a bedtime snack combining carbohydrates, protein, and fat works best for preventing overnight drops, especially when your blood sugar before bed is below 130 mg/dL.
Aim for 15 to 30 grams of carbohydrates paired with a serving of protein. Some practical combinations:
- Cereal with milk (covers carbs, protein, and a little fat)
- Crackers with peanut butter
- A quarter cup of hummus with half a pita
- A small whole wheat bagel with nut butter
- Half a cup of cottage cheese with half a banana
The protein and fat slow the release of glucose from the carbohydrates, providing a steadier fuel source through the night rather than a quick spike that fades by 2 a.m.
When a Low Becomes an Emergency
Severe hypoglycemia means your blood sugar has dropped so low that you can’t treat yourself. You might become confused, lose coordination, or lose consciousness entirely. This requires help from someone else.
If someone near you passes out from low blood sugar and can’t eat or drink, they need emergency glucagon. Modern options have made this much simpler than the old mixing kits. A nasal glucagon powder sprays into the nose like a nasal decongestant, with no injection required. Auto-injector pens work similarly to an EpiPen and go under the skin of the arm, stomach, or thigh. Both are designed so someone with no medical training can use them.
If you take insulin or medications that carry a risk of severe lows, keeping one of these glucagon options at home and making sure the people around you know where it is and how to use it can be lifesaving. After glucagon is given and the person regains consciousness, they should eat something substantial as soon as they’re able to swallow safely.