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What to do if…
your blood sugar reading is low and keeps dropping despite eating

Produced and maintained by PanicStation.org Published: Last reviewed: Editorial policy UK guide

Short answer

Treat a low reading as urgent: take fast-acting sugar now, re-check in 10–15 minutes, and repeat if it is still low. Call 999 now if you are becoming confused, very drowsy, unable to swallow safely, have had a seizure or blackout, are not responding normally, or it keeps dropping despite repeated fast sugar.

Do not do these things

  • Do not drive, cycle, or operate anything risky.
  • Do not go to sleep while it is low or still dropping.
  • Do not wait it out if the number keeps falling or symptoms are getting worse.
  • Do not take extra insulin or other glucose-lowering medicine while you are actively low, unless your diabetes team has specifically told you to.
  • Do not start with slow foods such as chocolate, biscuits, milk, or high-fat snacks; they can act too slowly for the first treatment.
  • Do not drink alcohol.
  • Do not force food or drink if you are very drowsy, choking, fitting, unconscious, or might pass out.

What to do now

  1. Get to a safer pause and get help nearby. Sit or lie down. If you are alone, call someone to come to you now and keep your phone unlocked. If you feel faint or confused, get onto the floor to reduce fall risk.
  2. Confirm the reading quickly if you can. In the UK, a blood glucose reading below 4.0 mmol/L is usually treated as low. If you use a CGM or flash monitor and the reading is dropping fast, or your symptoms do not match the sensor reading, do a finger-prick check if you can, but do not delay treatment if you feel low.
  3. Take fast-acting sugar now, choosing one option you can swallow safely:
    • glucose or dextrose tablets
    • glucose gel
    • a small glass of fruit juice
    • a regular, non-diet fizzy drink
    • a measured portion of sugary sweets
  4. Use the amount your diabetes team has told you to use. If you do not have a personal plan, a typical adult treatment is about 15–20g of fast-acting carbohydrate.
  5. Re-check in 10–15 minutes. If it is still below 4.0 mmol/L, or still falling, take another fast-acting sugar treatment and re-check again after 10–15 minutes.
  6. Call 999 now if any of these apply:
    • you are becoming confused, very drowsy, unable to swallow safely, or not responding normally
    • you have had a seizure or blackout
    • you cannot keep sugar down because of vomiting or retching
    • you are alone and symptoms are getting worse
    • it keeps dropping despite repeated fast sugar and you cannot get immediate clinical help
  7. While waiting for help, unlock the door if you can, sit or lie down, keep the fast sugar beside you, and keep re-checking only if you are able.
  8. If this is happening to someone else and they become too drowsy to swallow, unconscious, or fitting:
    • do not give food or drink by mouth
    • put them in the recovery position
    • give glucagon if it is available and someone knows how to use it
    • call 999
  9. Once you are clearly improving and can eat safely, have a longer-acting carbohydrate, especially if your next meal is not due soon, unless your diabetes team has told you otherwise. Examples include toast, a sandwich, cereal, crackers, or your next meal if it is due.
  10. After you are stable, get same-day advice if this was hard to treat. Contact your diabetes team or GP urgently if you take insulin or a sulfonylurea, if your levels keep dipping again, or if this was unusual for you. Use NHS 111 if you need urgent advice and are not sure which service to use. Call 999 for severe symptoms.

What can wait

  • You do not need to work out the exact cause right now.
  • You do not need to change insulin doses, pump settings, or diabetes medicines while you are actively low and dropping, unless a clinician or your written care plan tells you to.
  • You do not need to eat a full meal before treating the low; quick sugar and re-checking come first.
  • You do not need perfect notes. A simple record of times, readings, symptoms, and what you took is enough once you are safer.

Important reassurance

A dropping low can feel frightening and can cause shaking, sweating, anxiety, and confusion. Needing repeated quick sugar, help from another person, or emergency support is a safety issue, not a personal failure.

Scope note

These are first steps for the next few minutes to reduce immediate harm. Recurrent lows, severe lows, night-time lows, or lows that are hard to treat need follow-up with your diabetes team, GP, or urgent care service after you are safe.

Important note

This guide is general information, not a diagnosis or personal medical advice. If your reading will not rise despite repeated fast sugar, you cannot swallow safely, you are not responding normally, or you have severe symptoms, seek emergency help immediately.

Additional Resources

Closely connected guides that may be useful during the same situation or its immediate aftermath.

About this guide

This guide was produced and is maintained by PanicStation.org using its published editorial process. Official and specialist sources are checked where relevant, and AI-assisted tools may be used for drafting, organisation, and consistency checks. The site operator remains responsible for publication, revision, and removal decisions.

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