Here are my dietitian tips for how to reduce blood sugar level immediately, and what to do in extreme circumstances.
As a diabetes dietitian who also has diabetes myself, I know how frustrating it can be when your blood sugar is high. While there isn’t a one size fits all answer for lowering blood sugar immediately, I have used certain strategies over the years with clients (and myself) to help lower blood sugars both immediately and over time. We will discuss these below.
*This article is not intended to provide medical advice, diagnosis, opinion, treatment or services. The article and the links contained in it provide general information for educational purposes only. The information provided in this article is not a substitute for medical care. Do not use it in place of the advice of your physician or registered dietitian.*
What are normal blood sugar levels?
Here are some definitions of what “normal blood sugar” means for people without diabetes:
| Type of Test | When It’s Taken | Blood Sugar Level |
| A normal “fasting” blood glucose | first thing in the morning after waking up | 99 mg/dL or lower |
| A random blood glucose test | any time of the day without regard to the last time you’ve eaten | should be under 200 mg/dL |
If you have diabetes (any type), your doctor will discuss specific blood sugar goals with you. These goals can vary based on a variety of factors.
Diabetes blood sugar levels for diagnosis
Diabetes is often diagnosed with blood glucose tests in any of the following levels:
| Type of Test | Blood Glucose Levels to Diagnose Diabetes |
| Fasting blood glucose | 126 mg/dL or higher (100-125 mg/dL is considered pre-diabetes) |
| Random blood glucose | 200 mg/dL or higher |
What is high blood sugar for people with diabetes?
If you live have diabetes, and your blood sugar is above the following levels, it’s time to take action based on what your diabetes care team has told you. These levels are considered hyperglycemia in diabetes and should be discussed with your doctor or diabetes educator.
| Type of test | Blood glucose level |
| 1-2 hours after eating | >180 mg/dL |
| Fasting | >126 mg/dL |
How to reduce blood sugar level immediately
How to lower blood sugar immediately can depend on a variety of factors. The following strategies are almost always helpful and are explained further below:*
- Go for a walk**
- Drink a large glass of water
- Take rapid-acting insulin if directed by your doctor
1. Go for a walk to reduce blood sugar level immediately
Light to moderate activity when your blood sugar is high may be helpful in bringing it down immediately. A moderate paced 15-30 minute walk (faster than a stroll, but not speed walking) can be helpful in reducing blood sugar. You can also try other light activities, such as gardening or swimming.
2. Drink a large glass of water to reduce blood sugar level immediately
Sometimes, your blood sugar may be elevated because of dehydration. Less water in your blood stream means the sugar in your blood is more concentrated. Staying properly hydrated or drinking water when your are dehydrated can help to increase the liquid in your blood stream, and thus lower blood sugar.
3. Take rapid acting insulin as directed by your doctor to reduce blood sugar level immediately
If you have type 1 diabetes or insulin dependent type 2 diabetes, your doctor has likely given you an insulin dosing plan for when your blood sugar is high. Taking rapid acting insulin as directed can lower blood sugar immediately.
This is often done with something called a sensitivity factor or correction factor. A correction factor is a number given to you by your doctor that you use to determine how much insulin to take when your blood sugar is high. Let’s look at a hypothetical example…
- Blood glucose value: 200mg/dL
- Target blood glucose value: 120 mg/dL
- Correction factor: 40
In this scenario, the blood sugar is 80 points above target. We divide the difference between our high blood sugar (200mg/dL) and the target blood sugar (120mg/dL) by the correction factor (40). In this case, it would be 80 divided by 40 which equals 2. So, this person would take 2 units of insulin to correct their high blood sugar.
Speak with your doctor and care team to learn what your correction factor should be.
How to reduce blood sugar level immediately for EXTREMELY HIGH blood sugar
*Extremely high blood sugar (>250mg/dL) can be a life-threatening situation if ketones are also present. Diabetic ketoacidosis (DKA) can develop when blood sugars reach this level. Discuss your plan of action with your doctor if/when this happens. Know when to stay home and manage your blood sugar, and when to go to the emergency room.
**Exercise may not be appropriate if blood sugars are >250mg/dL. Discuss this with your doctor before trying to exercise when your blood sugar is this high.
When to go to the emergency room with high blood sugar
You should seek emergency help if ketones become too high in your blood stream to avoid DKA. There is no set number of high blood sugar that leads to ketones, but you are at a greater risk when blood sugars are >250mg/dL for an extended period of time. Monitor ketones at home every few hours when blood sugars are high and seek emergency help in the following situations:
- Urine ketone test strips show moderate or large ketones
- Blood ketone meter registers 1.6mmol/L or higher
Ketone Levels and DKA Symptoms
These levels of ketones can lead to DKA (diabetic ketoacidosis). Symptoms of DKA include:
- Excessive thirst or dry mouth
- Frequent urination
- Flushed red skin
- Extreme fatigue
- Nausea or vomiting
- Confusion
- Shortness of breath
- A fruity smell on the breath
Speak with your doctor about when they want you to seek emergency help.
Lowering blood sugar immediately vs. over time
What you should do with elevated blood sugars in the moment is different than discussing what foods help lower blood sugar over time. This discussion is often more relevant to people on insulin (type 1 diabetes and insulin-dependent type 2 diabetes) but can apply to all forms of diabetes.
If you’re interested to learn about specific foods that can help lower blood sugar, I have another post that covers each of the foods I recommend.
For more resources on managing diabetes and balancing blood sugars, check out the Diabetes 101 section of my website. We cover a variety of topics all related to balancing blood sugars!
This article was further updated from June 2023, and complements the other article What Foods Lower Blood Sugar Immediately + Meal Ideas.
References:
- Diabetes Diagnosis, Mayo Clinic. (2023) https://www.mayoclinic.org/diseases-conditions/diabetes/diagnosis-treatment/drc-20371451
- Type 1 Diabetes, Mayo Clinic. (2023) https://www.mayoclinic.org/diseases-conditions/type-1-diabetes/diagnosis-treatment/drc-20353017
- 10 Surprising Things That Can Spike Your Blood Sugar, Centers for Disease Control and Prevention. (2022) https://www.cdc.gov/diabetes/library/spotlights/blood-sugar.html
