Home / Resources / Clinical Gems / Diabetic Emergencies, Diagnosis and Clinical Management: Sick-Day Rules in Diabetes, Part 2

Diabetic Emergencies, Diagnosis and Clinical Management: Sick-Day Rules in Diabetes, Part 2

Feb 25, 2013
Konstantinos Makrilakis, Nikolaos Katsilambros
In patients taking insulin — either basal only ( ± pills) or a more intensified regimen (insulin mixtures two or three times daily or a basal-bolus regimen) — the “sick-day rules” should be taught and the patient should be provided with urine strips to test for ketones (e.g., Ketostix) and rapid-acting soluble insulin (human or insulin analog) along with their usual insulin and blood glucose testing kit.12

Glucagon injection should also be available at home for family members to use in case of severe hypoglycemia. They should also have clear “contact criteria” and contact telephone numbers for their health care provider team (see “Patient advice” below).


For patients following an intensified insulin regimen (usually Type 1 diabetic patients) the insulin regimen is followed, basically, as it is, provided the patient is feeding normally. If needed, the doses of “prandial” and basal insulin are increased, based on frequent blood glucose measurements. Sometimes it may be necessary to administer rapid-acting insulin (or even better a rapid-acting insulin analog) in between meals. In this case, small doses are preferred. If the patient is unable to take food (due for example to nausea/vomiting), the dose of basal insulin is administered normally and, if needed, rapid-acting insulin is administered every 4-6 hours, or a rapid-acting analog every 3-4 hours.14 At the same time, intake of carbohydrates in the form of liquid or semi-solid food (i.e., juice, refreshments, soups, purée, etc.) is recommended. Insulin dose is empirically determined each time as 1/10th of the usual total daily dose when blood glucose is > 150 mg/dl (8.3 mmol/L), or as 1/5th of the total daily dose when blood glucose is > 200 mg/dl (11.1 mmol/L) or urine ketones are present. It is advisable to give specific numbers with examples and not just percentages. For instance, if the patient is using 40 IU insulin in total, they should administer 4 IU regular insulin if blood sugar is > 150 mg/dl (8.3 mmol/L) and 8 IU when blood glucose is > 200 mg/dl (11.1 mmol/L).
  • In patients taking insulin, the “sick-day rules” should be taught in advance and patients should be provided with urine strips to test for ketones (e.g., Ketostix) and rapid-acting soluble insulin (human or insulin analog) along with their usual insulin and blood glucose testing kit.
When insulin is administered as a twice-a-day regimen (intermediate-acting or a mixture of rapid-acting [or analog]/ intermediate-acting, in the morning and evening), this scheme is initially preserved as it is if the patient is eating normally, additional rapid-acting (or rapid-acting analog) insulin may be administered in between, based on blood glucose measurements. If the patient is unable to eat (for example due to nausea/vomiting), a decrease in the insulin dose by 30-50% is recommended initially, as well as close monitoring of blood glucose levels, intake of carbohydrates in the form of liquid or semi-solid food, and possibly administration of rapid-acting (or analog) insulin.10 If the condition persists, it may be necessary to admit the patient to the hospital.

For patients taking pills, when diabetes is under good control (and theoretically there is adequate endogenous insulin reserve) there is usually not a great problem during an acute illness. There may be a mild rise in blood glucose during the period of acute illness, later returning to previous normal levels. If, however, blood glucose levels become high (usually > 200 mg/dl [11.1 mmol/L]) or symptomatic, then a temporary period of insulin treatment with frequently repeated soluble insulin doses may be needed. People taking metformin should stop the drug during episodes of illness requiring hospital admission or confining them to bed (due to the potential risk of lactic acidosis).

Follow-up management/care

As people get better and blood sugars improve and/or ketonuria resolves, they should reduce their insulin back towards their usual dose (or, for patients who were previously on an oral antidiabetic regimen, stop insulin completely), guided by blood glucose measurements.

On the other hand, if the condition deteriorates, patients/family members should be prepared to go to the emergency room for urgent care. Criteria for transfer to the hospital are the following:

  1. When poor glycemic control is accompanied by an alteration in the level of consciousness
  2. Ketonuria or ketonemia are present and persist for more than 6 hours, despite the administration of insulin, carbohydrates, and fluids
  3. Blood glucose levels > 400 mg/dl (22.2 mmol/L) in > 2 repeated measurements, despite the administration of rapid-acting insulin
  4. Inability to receive hydration by mouth.


  • If the condition deteriorates, patients/family members should be prepared to go to the emergency room for urgent care.
Patient advice

Instructions to patients should be given beforehand, so that they are prepared to cope with an acute event. Written instructions are preferred. Some scientific organizations have written advice on their website (e.g., http://www.diabetes.org.uk/).

An example follows:

People with diabetes do not have more illness than others but if you do become unwell, it is likely that your blood glucose control will be upset. When you are sick, your body will release hormones that work to help your body fight against your illness, but they will also make your blood sugar levels rise. This means that your diabetes will be more difficult to control when you are sick. That is why it is so important to plan ahead and be prepared in case of illness. Sickness can include: a cold, flu-like symptoms such as vomiting, diarrhea, sore throat, and infections such as ear, teeth, or bladder, or more serious illnesses such as pneumonia or a foot infection.

When to call your doctor

Minor illnesses in people with diabetes — especially children with Type 1 diabetes — can lead to very high blood sugar levels and possible emergencies. When children are sick, watch them closely for signs that they need immediate medical attention. Call your doctor or other emergency services if you or your child has:

  • Symptoms of diabetic ketoacidosis (DKA), such as abdominal pain, vomiting, rapid breathing, fruity-smelling breath, or severe drowsiness.
  • Symptoms of dehydration, such as a dry mouth and very yellow or dark urine. Dehydration is particularly dangerous in children and elderly persons and may be caused by vomiting and diarrhea.
  • A low blood sugar level ( < 70 mg/dl [3.9 mmol/L]) that continues.

It may not be necessary to call your doctor every time you or your child with diabetes has a mild illness, such as a cold. But it is a good idea to call for advice when you are sick and:

  • Your blood sugar level is higher than 240 mg/dL (13.3 mmol/L) after taking the adjusted amount of insulin in your sick-day plan
  • You take oral diabetes medicine and your blood sugar level is higher than 240 mg/dL (13.3 mmol/L) before meals and stays high for more than 24 hours
  • You have more than 2 + or moderate ketones in your urine
  • You still have a fever and are not feeling better after a few days
  • You are vomiting or having diarrhea for more than 6 hours.

When you are sick, write down the medicine(s) you have been taking and whether you have changed the dosage of your diabetes medicines based on your sick-day plan. Also note changes in your body temperature, weight, blood sugar, and urine ketone levels. Have this information handy when you talk to your doctor.

Plan ahead — steps to take during an illness

Some general sick-day guidelines:

  • Continue taking your pills for diabetes (if you have Type 2 diabetes) or insulin, even if you are vomiting and having trouble eating or drinking. Your blood sugar may continue to rise because of your illness. If you cannot take your medicines, call your doctor and discuss whether you need to adjust your insulin dose or other medicines. Metformin should be stopped if you are becoming dehydrated.
  • Try to eat your normal types and amounts of food and to drink extra fluids, such as water, broth, carbonated drinks, and fruit juice. Encourage your child or loved one with diabetes to drink extra liquids to prevent dehydration.
  • If your blood sugar level is higher than 240 mg/dl (13.3 mmol/L), drink extra liquids that do not contain sugar, such as water or sugar-free soft drinks.
  • If you cannot eat the foods in your regular diet, drink extra liquids that contain sugar and salt, such as soup or milk. You may also try eating foods that are gentle on the stomach, such as crackers, gelatin, or apple sauce. Try to eat or drink 50 grams (g) of carbohydrate every 3 to 4 hours. For example, 6 saltine crackers, 1 cup of milk, and ½ cup (4 fl oz) of orange juice each contain approximately 15 g of carbohydrate.
  • Check your blood sugar at least every 3 to 4 hours, or more often if it is rising quickly, even through the night. If your blood sugar level rises above 240 mg/dL (13.3 mmol/L) and your doctor has told you to take an extra insulin dose for high blood sugar levels, take the appropriate amount. If you take insulin and your doctor has not told you to take a specific amount of additional insulin, call him or her for advice.
  • If you take insulin, do a urine test for ketones every 4 to 6 hours, especially if your blood sugar is higher than 270 mg/dL (15.0 mmol/L). Call your doctor if you have more than 2 + or moderate ketones in your urine.
  • Weigh yourself and check your temperature, breathing rate, and pulse frequently if your blood sugar is higher than 300 mg/dL (16.7 mmol/L). If you are losing weight and your temperature, breathing rate, and pulse are increasing, contact a doctor. You may be getting worse.
  • Don’ t take any non-prescription medicines without talking with your doctor. Many non-prescription medicines affect your blood sugar level.
Next Excerpt: Chapter 8 Sick – Day Rules in Diabetes (Part 3) Case Studies

10. Liatis S. Acute illness in diabetes In: Katsilambros N , Diakoumopoulou E , Ioannidis I , Liatis S , Makrilakis K , Tentolouris N , Tsapogas P (ed), Diabetes in Clinical Practice, Questions and Answers from Case Studies , West Sussex, England : John Wiley & Sons Ltd , 2006: 103-7 .

11. Laffel LM , Wentzell K , Loughlin C , Tovar A , Moltz K , Brink S . Sick day management using blood 3-hydroxybutyrate (3-OHB) compared with urine ketone monitoring reduces hospital visits in young people with T1DM: A randomized clinical trial. Diabet Med 2006; 23: 278-84.

12. Weber C, Kocher S, Neeser K, Joshi SR. Prevention of diabetic ketoacidosis and self-monitoring of ketone bodies: An overview. Curr Med Res Opin 2009; 25: 1197-207.

13. Cahill GF Jr. Fuel metabolism in starvation. Annu Rev Nutr 2006; 26: 1-22.

14. Bolli GB. Insulin treatment and its complications. In: Pickup JC , Williams G (ed), Textbook of Diabetes Mellitus , 3rd ed., Oxford, UK: Blackwell Publishing , 2003: 43.1-38.

Nikolaos Katsilambros, MD, PhD, FACP
SCOPE Founding Fellow
Professor of Internal Medicine
Athens University Medical School
Evgenideion Hospital and Research Laboratory ‘Christeas Hall’
Athens, Greece
Christina Kanaka-Gantenbein, MD, PhD
Associate Professor of Pediatric Endocrinology and Diabetology
First Department of Pediatrics, University of Athens
Agia Sofia Children’s Hospital
Athens, Greece
Stavros Liatis, MD
Consultant in Internal Medicine and Diabetology
Laiko General Hospital
Konstantinos Makrilakis, MD, MPH, PhD
Assistant Professor of Internal Medicine and Diabetology
Athens University Medical School
Laiko General Hospital
Athens, Greece
Nikolaos Tentolouris, MD, PhD
Assistant Professor of Internal Medicine and Diabetology
University of Athens
Laiko General Hospital
Athens, Greece
A John Wiley & Sons, Ltd., Publication This edition first published 2011 © 2011 by John Wiley & Sons, Ltd.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the publisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. The contents of this work are intended to further general scientific research, understanding, and discussion only and are not intended and should not be relied upon as recommending or promoting a specific method, diagnosis, or treatment by physicians for any particular patient.
Diabetic Emergencies: Diagnosis and Clinical Management provides emergency room staff, diabetes specialists and endocrinologists with highly practical, clear-cut clinical guidance on both the presentation of serious diabetic emergencies like ketoacidosis, hyperosmolar coma and severe hyper- and hypoglycemia, and the best methods of both managing the emergencies and administering appropriate follow-up care.
For more information and to purchase this book, just follow this link: Diabetic Emergencies: Diagnosis and Clinical Management