Keeping blood sugar levels within a healthy range is important for managing diabetes. There may be times when blood sugar levels spike unexpectedly high. Getting them back down quickly can help prevent ongoing high blood sugar and complications related to hyperglycemia.
What causes high blood sugar?
Blood sugar levels go up when there is too much glucose (sugar) in the bloodstream. This can happen for a few reasons:
- Eating more carbohydrates than the body can process
- Not taking enough insulin or diabetes medications
- Being physically inactive
- Being ill or stressed
- Taking certain medications that raise blood sugar
In people with diabetes, the body has difficulty regulating blood sugar on its own. So blood sugar levels can sometimes rise too high after meals, during illnesses, or due to insulin resistance. Keeping levels in check involves carefully balancing food, activity, and medication.
What are symptoms of high blood sugar?
Symptoms of high blood sugar may include:
- Increased thirst and dry mouth
- Frequent urination
- Fatigue
- Blurred vision
- Stomach pains or nausea
- Shortness of breath
- Fruity odor on the breath
However, symptoms can vary between people. Some people with diabetes do not experience any symptoms when blood sugar is high. Checking blood sugar levels regularly can help detect hyperglycemia.
When to bring blood sugar down immediately
Treatment guidelines generally recommend correcting high blood sugar levels above 180-250 mg/dL. Lowering blood sugar quickly is especially important when levels are:
- Over 300 mg/dL
- Over 250 mg/dL for more than 2 readings in a row
- Over 180 mg/dL along with symptoms of hyperglycemia
In these cases, taking swift action can help prevent diabetic ketoacidosis (DKA), severe dehydration, and other dangerous complications.
How to lower blood sugar quickly
Here are some of the most effective ways to lower high blood sugar right away:
1. Take fast-acting insulin
Fast-acting insulin brings blood sugar down the fastest. It starts working within 15 minutes and peaks within 1-2 hours. Taking a correction dose or additional bolus dose with a meal can help lower blood sugar when it is high.
Work with your healthcare provider to determine your insulin-to-carb ratio and correction factor. These will tell you how much additional insulin to take based on your blood sugar reading and grams of carbohydrates eaten.
2. Drink water
Staying hydrated helps dilute excess sugar in the bloodstream. Aim to drink at least 8 ounces of water right after checking your blood sugar. Sipping on water throughout the day can also prevent dehydration from frequent urination.
3. Exercise
Physical activity can help stimulate insulin absorption and lower blood sugar levels. Going for a walk, jog, swim, or bike ride for 20-30 minutes can bring levels down. However, intense exercise is not recommended when blood sugar is over 300 mg/dL.
4. Take oral diabetes medications
Oral medications like metformin, glipizide, or glimepiride can help lower blood sugar. Taking an extra dose with a meal as prescribed by your doctor can help control post-meal spikes. These medications take 1-2 hours to start working.
5. Inject GLP-1 agonists
GLP-1 agonists like liraglutide and exenatide are injected medications that stimulate insulin release. They can begin working in 2-5 minutes to lower blood sugar after a meal. They are faster-acting than most oral medications.
6. Adjust your next meal
Choose lower-carb foods for your next meal to prevent additional spikes. Focus on non-starchy vegetables, proteins, fats, and high-fiber foods. Limit carbohydrate-heavy foods like bread, pasta, rice, and sweets.
7. Check ketones
When blood sugar is over 250 mg/dL, check urine or blood ketones. High ketones indicate insulin deficiency and increased risk of DKA. Call your healthcare provider if ketones are elevated.
| Blood Ketone Level | Urine Ketone Level | Action Needed |
|---|---|---|
| Less than 0.6 mmol/L | Negative | Recheck in several hours if blood sugar remains high |
| 0.6 to 1.4 mmol/L | Small to Moderate | Drink water, take insulin correction dose |
| Over 1.4 mmol/L | Large | Seek emergency medical care |
When to go to the ER for high blood sugar
Seek emergency care if:
- Blood sugar is over 300 mg/dL and stays high after taking correction doses of insulin and medications
- Moderate or large ketones are present
- You are vomiting and unable to keep down fluids or medications
- You have symptoms of hyperglycemic hyperosmolar nonketotic syndrome (HHNS) like dry mouth, extreme thirst, severe dehydration, vision changes, confusion, or loss of consciousness
Going to the ER allows doctors to provide IV fluids, electrolyte replacement, insulin, and other treatments for severe hyperglycemia.
How to prevent severe high blood sugar
While it’s normal to occasionally experience highs, some strategies can help avoid severe spikes:
- Check blood sugar regularly – at least before meals and at bedtime, more often if taking insulin
- Take diabetes medications as prescribed
- Carry supplies to treat low blood sugar in case of overcorrection
- Learn how different foods impact your blood sugar
- Stay hydrated and avoid excessive alcohol intake
- Manage stress through exercise, meditation, or speaking with a therapist
- See your healthcare provider regularly to review medications and glucose targets
High blood sugar can happen sometimes no matter how careful you are. Having an action plan in place makes it easier to respond appropriately and get levels back in range promptly.
Conclusion
Lowering high blood sugar quickly is important for preventing short-term and long-term diabetes complications. When over 250 mg/dL or with symptoms, taking fast-acting insulin, drinking fluids, exercising, and making meal adjustments can help correct hyperglycemia. Seek emergency care for very high sugars, moderate-large ketones, or dehydration. Staying on top of daily management while having an emergency action plan makes it easier to get blood sugar under control fast.