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Symptoms of high blood sugar

Many people struggle with high blood sugar and find it hard to keep their diabetes under control. Here are the symptoms of high blood sugar so you can tell if you need to speak to your doctor about adjusting your medication. If you have high blood sugar and risk factors of Type 2 diabetes, you may be able to reverse it: here’s how to do it.

What is high blood sugar?

symptoms of high blood sugar

High blood sugar (hyperglycaemia) happens when glucose levels rise above 10mmol/L. (Here’s a reminder of what normal blood sugar is.) This can be because of food (eating foods with too much sugar or carbohydrates), or medication (either not injecting enough insulin or being on the wrong dose of oral medication). Metformin is a common oral medication that helps to reduce insulin resistance. You will often have high blood sugar before you are diagnosed with diabetes.

How insulin works

Insulin is taken by all people with Type 1 diabetes (either in injections or with an insulin pump). It can also be taken by people with Type 2 diabetes if their doctors recommend it. Insulin is like a key that allows glucose to pass from the blood stream into the cells to give the body energy. Without insulin, glucose sits in the blood stream where it is not supposed to be, and causes high blood sugar.

Symptoms of high blood sugar

Different people will have different symptoms of high blood sugar.

  • Many people feel very thirsty: the blood is so full of glucose that the body tries to dilute it with water by making you drink more water.
  • This will also make you need to pee more often.
  • It is common to feel tired when blood sugar levels are high because not enough glucose is getting into the body’s cells (from the blood) to give the body energy. Instead, it is sitting in the blood stream.
  • Many people experience headaches and blurry vision too.
  • Weight loss happens when blood sugar levels are left to run high for a long time. The body is starved of energy because the glucose cannot enter the cells from the blood.
  • Nausea and vomiting can be a sign of dangerously high blood sugar.

Do you have any of these symptoms of high blood sugar? If your blood sugar is consistently high and you can’t get it down, it’s important to go to your doctor or clinic.

Laura Pirjol is a 6th year medical student who blogs on Instagram about the highs and lows of living with diabetes. Check her out at @highs_and_lows_97. We asked her to outline some of the symptoms of high blood sugar.

What to read next?

What is normal blood sugar? An explanation of what the normal range of blood sugar is, and what people with diabetes can do to achieve those numbers.

How to reverse Type 2 diabetes: A step-by-step guide to reversing Type 2 diabetes, as simply as possible.

What is insulin resistance? Understanding what insulin resistance is, and what to do about it.

What to read next
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Sweet Life is a registered NPO/PBO (220-984) with a single goal: to improve diabetes in South Africa. We are funded by sponsorships and donations from aligned companies and organisations who believe in our work. We only share information that we believe benefits our community. While some of this information is linked to specific brands, it is not an official endorsement of that brand. We believe in empowering people with diabetes to make the best decisions they can, to live a healthy, happy life with diabetes.