Knowing the difference between a hypo and a hyper — and what to do in each case — can prevent a minor episode from becoming a serious emergency.
Blood glucose below 4 mmol/L
Symptoms: shaking, sweating, pale skin, confusion, palpitations, irritability, hunger, dizziness
Onset: Can come on very quickly — minutes
Blood glucose above 11 mmol/L
Symptoms: thirst, frequent urination, fatigue, headache, blurred vision, fruity breath (ketones), nausea
Onset: Develops over hours to days
If the person is conscious and can swallow:
Choose one of the following:
• 150–200ml of fruit juice or regular (non-diet) fizzy drink
• 4–5 glucose tablets (such as Glucotabs)
• 3–4 teaspoons of sugar dissolved in water
• 5–6 jelly babies
• Small tube of glucose gel (Glucogel)
Check blood glucose after 15 minutes. If still below 4 mmol/L, repeat the fast-acting glucose. Do this up to 3 times.
Once blood glucose is above 4 mmol/L and the person feels better, give a longer-acting carbohydrate snack to prevent a second hypo: a few biscuits, a sandwich, or their next meal if it is due.
If the person is unconscious, place in the recovery position and call 999. Emergency services may administer glucagon.
Mild to moderate hyperglycaemia often resolves with medication and hydration. However, severe hyperglycaemia can develop into diabetic ketoacidosis (DKA) in Type 1 diabetes, or hyperosmolar hyperglycaemic state (HHS) in Type 2 — both of which are medical emergencies.
For mild hyperglycaemia (11–15 mmol/L, well, not in distress):
Call 999 or go to A&E urgently if the person has:
If you are caring for someone with diabetes, make sure you know:
Was this guide helpful?
Contact Ekvarta on WhatsApp or email — a real person responds, not a chatbot.