What are the symptoms of hypoglycaemia?

Symptoms of hypoglycaemia can include shakiness, sweating, hunger, dizziness, blurred vision, irritability, confusion, and weakness. Hypoglycaemia means that blood glucose has fallen too low for your body to function comfortably. Symptoms may come on quickly and can differ from one episode to another.

Early warning signs are often physical: a fine tremor, clammy sweating, a racing heartbeat, sudden hunger, tingling around the lips, tiredness, or feeling light-headed. You may also become anxious, irritable, or unable to concentrate. Some people notice a [Tremor](/symptoms/tremor/) or [Dizziness](/symptoms/dizziness/) before they recognise the cause.

As glucose falls further, thinking and coordination can be affected. You might speak unclearly, behave unusually, have trouble seeing clearly, become very drowsy, or have a seizure. A person with severe symptoms may lose consciousness and cannot safely treat themselves.

Hypoglycaemia is especially relevant for people using insulin or certain diabetes medicines, including people with [Type 1 Diabetes](/conditions/type-1-diabetes/) or [Type 2 Diabetes](/conditions/type-2-diabetes/). It can also happen after missed meals, strenuous activity, alcohol, or illness. Symptoms alone cannot confirm the cause; checking glucose when possible is useful.

If you are awake and able to swallow, stop what you are doing, sit down, and take a fast-acting source of sugar such as glucose tablets or a sugary drink. Recheck your glucose after a short interval if you have a meter, and repeat the treatment if it remains low or symptoms continue. Once you feel better, eat a snack or meal containing longer-lasting carbohydrate if your next meal is not soon.

Do not drive, exercise, or make important decisions while symptoms are present. Tell someone nearby what is happening. If episodes recur, arrange a [GP Consultation](/treatments/consultations-and-assessment/gp-consultation/) to review medicines, meals, activity, alcohol, and glucose records. A [Diabetes Education Programme](/treatments/lifestyle-and-wellness/diabetes-education-programme/) can help you recognise patterns and prepare a personal action plan.

Call emergency services if someone is unconscious, having a seizure, severely confused, or unable to swallow. Do not give food or drink to an unconscious or drowsy person because they may choke. Place them on their side, stay with them, and tell responders that low blood sugar is possible.

Seek prompt medical advice if symptoms do not improve after treatment, keep returning, occur when you do not use diabetes medicine, or happen during pregnancy. A clinician can check for medication effects and other causes. Read more about [Hypoglycaemia](/conditions/hypoglycaemia/).

Ask which symptoms should prompt you to check your glucose, how to adjust your treatment plan safely, and whether you should carry glucose tablets or use a prescribed rescue medicine. Bring a record of symptoms, glucose readings, meals, exercise, alcohol, and medicine timing.