Hypoglycemia (Low Blood Sugar)

What is hypoglycemia?

Hypoglycemia, commonly called a hypo or low blood sugar, is when the level of glucose (sugar) in the blood falls too low. Glucose is the body's main source of energy, and the brain in particular depends on a steady supply, so when levels drop too far, the body produces warning symptoms and, if not corrected, function can be affected. It is most commonly associated with diabetes, but can occasionally occur for other reasons.

In people with diabetes, hypoglycemia usually happens as a side effect of treatments that lower blood sugar, such as insulin or certain tablets, when the balance between medication, food and activity tips too far. It is one of the most important things for people on these treatments to understand and be prepared for. Most hypos are mild and easily treated by taking sugar, but because a severe low can be dangerous, knowing the signs and how to respond quickly is essential.

Symptoms

The symptoms of hypoglycemia come on relatively quickly and act as warning signs that blood sugar is dropping and needs correcting. They can include:

• •Feeling shaky or trembling
• •Sweating
• •Feeling hungry
• •Tingling lips
• •Feeling anxious, irritable or tearful
• •A fast or pounding heartbeat
• •Dizziness, difficulty concentrating, or confusion
• •In severe cases: slurred speech, unusual behaviour, seizures, or loss of consciousness

Causes

Hypoglycemia occurs when there is too much glucose-lowering effect relative to the glucose available. In people with diabetes, this is usually related to their treatment and its balance with food and activity. Causes and triggers include:

• •Taking too much insulin or certain diabetes medicines relative to needs
• •Missing or delaying a meal, or eating less carbohydrate than usual
• •More physical activity than usual without adjusting food or medication
• •Drinking alcohol, especially without food
• •Less commonly, hypoglycemia in people without diabetes, from various causes

How to treat a hypo

Treating hypoglycemia quickly is important, and the approach for a conscious person who can swallow is to take fast-acting sugar straight away. This means something that raises blood sugar quickly, such as glucose tablets, a sugary (non-diet) drink, or fruit juice. After taking the fast-acting sugar, waiting a short time, and checking blood sugar again if able, it is usually recommended to follow up with a longer-acting carbohydrate snack, such as a sandwich or biscuits, to keep blood sugar stable.

For a severe hypo, where the person is confused, unable to swallow safely, or unconscious, the situation is a medical emergency. They should not be given anything by mouth if they cannot swallow safely, because of the risk of choking. Instead, emergency help should be sought, and if the person has been prescribed emergency treatment (such as a glucagon injection) and someone is trained to give it, it should be used. People with diabetes at risk of severe hypos, and those around them, benefit from knowing this emergency plan in advance.

Preventing hypoglycemia

For people with diabetes on treatments that can cause hypos, prevention is an important part of day-to-day management. Key measures include eating regular meals with appropriate carbohydrate, not skipping meals, taking medication as prescribed and in balance with food and activity, and being especially mindful around exercise and alcohol, both of which can lower blood sugar. Monitoring blood sugar, as advised, helps spot and prevent lows.

It also helps to be prepared: people prone to hypos are usually advised to carry fast-acting sugar with them at all times, so they can treat a low promptly wherever they are. Recognising your own early warning signs, and acting on them quickly, prevents mild lows from becoming severe. Some people, over time, become less aware of the early symptoms of a hypo, which is important to discuss with a diabetes care team, as it needs particular attention.

For anyone experiencing frequent or severe hypos, or hypos that are hard to explain, it is important to speak with a doctor or diabetes team, as treatment may need adjusting. And for the uncommon situations where hypoglycemia occurs in someone without diabetes, medical assessment is needed to find the cause. With good management, most people at risk of hypos are able to prevent and treat them effectively, keeping blood sugar in a safe range.