Sick-Day Management for Type 1 Diabetes

Being unwell places extra stress on the body, and infections, fever, or even minor illnesses can quickly affect blood glucose levels. “Sick-day rules” are a set of steps that help you manage Type 1 diabetes safely during illness and reduce the risk of serious complications like diabetic ketoacidosis (DKA).

Core Rules

Never stop basal insulin — your body still needs background insulin, even if you are not eating.
Check blood glucose more often — every 2–4 hours (including overnight if unwell).
Check ketones whenever blood glucose is high (> 13–15 mmol/L) or if you feel unwell.
Follow your personalised sick-day action plan if you have one from your diabetes team.

Fluids & Carbohydrates

Stay hydrated with frequent small sips of water or sugar-free fluids.
If you cannot eat normally, take in sick-day carb options such as fruit juice, regular soft drink, honey, jelly, or glucose powder/tablets — these provide energy and help prevent ketosis.
Aim for ~50 g carbs every 3–4 hours if unable to manage normal meals.

Insulin Adjustments

Illness often raises insulin needs due to stress hormones.
Follow your plan for correction doses (injections) or temporary basal increases (pump).
If you are vomiting, or glucose levels stay high despite extra insulin, contact your diabetes team early.
Keep detailed notes of insulin doses, blood glucose, ketone results, and fluids taken.

Red Flags — Seek Urgent Medical Care

Call emergency services or go to hospital if you have:

Ketones ≥ 3.0 mmol/L, or rising ketones despite insulin and fluids.
Persistent vomiting or inability to keep fluids down.
Abdominal pain, rapid breathing, fruity breath, or drowsiness (possible DKA).
Severe dehydration (sunken eyes, very little urine, extreme thirst).

Extra Tips

Keep a sick-day kit stocked: ketone strips, glucose tablets, rehydration drinks, insulin supplies, thermometer, and contact numbers.
Inform close family, friends, or colleagues about your sick-day plan so they can assist if needed.
Review your sick-day rules annually with your diabetes team — update if your insulin regimen or devices change.

FAQ

Q: Should I stop insulin if I’m not eating?
A: No. Always continue basal insulin. Stopping insulin completely is dangerous and can trigger DKA.

Q: How do I manage nausea or vomiting?
A: Take small sips of fluid every few minutes, use carb-containing fluids if not eating, and monitor ketones closely. Seek help early if you can’t keep fluids down.

Q: Can illness cause blood glucose to go low instead of high?
A: Yes, especially if you are eating less. This is why frequent testing and adjusting insulin with guidance from your plan or team is essential.

⚠️ Remember: Sick-days carry higher risks for people with Type 1 diabetes.
Never stop insulin, keep checking glucose and ketones, stay hydrated, and seek medical help early if you are unable to control levels or keep fluids down.

Printable Checklist

You can download the one-page Sick-Day Checklist (PDF)
and keep it in your kit or on your fridge for quick reference.