High Blood Sugar Levels in the Morning? Dawn Phenomenon & Somogyi Effect Explained - CARiNG Pharmacy

High Blood Sugar Levels in the Morning? Dawn Phenomenon & Somogyi Effect Explained

Mr Ng is diabetic person, he usually has good blood sugar level control as he checks regularly after food. But one day he decides to check his blood sugar level before breakfastthe level shows 10 mmol/L! – the high level shocks him (refer to table 1). What’s the explanation behind a spike in early morning blood sugar levels? We explore the two common reasons of high blood sugar levels in the morning:

  • The Dawn Phenomenon
  • The Somogyi Effect

Image 2: Blood sugar level charts for people who experience the dawn phenomenon and the somogyi effect. 


Dawn Phenomenon

The dawn phenomenon is a normal rise in blood sugar as a person’s body prepares to wake up. In the early morning hours, hormones (growth hormone, cortisol, and catecholamines) cause the liver to release large amounts of sugar into the bloodstream. For most people, the body produces insulin to control the rise in blood sugar. If the body doesn’t produce enough insulin, blood sugar levels can rise. This may cause high blood sugar in the morning (before eating).


Somogyi Effect

If the blood sugar level drops too low in the early morning hours, hormones (such as growth hormone, cortisol, and catecholamines) are released. These help reverse the low blood sugar level but may lead to blood sugar levels that are higher than normal in the morning. 

An example of the Somogyi effect is:

  • A person who takes insulin doesn’t eat a regular bedtime snack, and the person’s blood sugar level drops during the night.
  • The person’s body responds to the low blood sugar by releasing hormones that raise the blood sugar level. This may cause a high blood sugar level in the early morning.


Are Both Conditions Harmful?

Yes, but a Somogyi effect may be the more harmful condition as blood sugar levels go much lower. Both events bring about complications related to low and high sugar levels.

  • Complications of low sugar levels – hypoglycemia (dizzy spells, palpitation, trembling, etc)
  • Complications of high sugar levels – hyperglycemia (blindness, nerve damage, heart attack, etc) 


How Can You Tell If You Suffer From The Dawn Phenomenon or Somogyi Effect?

Check blood sugar levels at bedtime, and at your normal wake-up time. If the levels are “off target”, you might be suffering from either the dawn phenomenon or the Somogyi effect. (See Table 1)

However, to distinguish if one is suffering from either the dawn phenomenon or the Somogyi effect, seek help from an endocrinologist (a specialist in diabetes). 

Table 1. Blood Sugar Level Targets Before Bed & Upon Waking


How Do I Avoid The Dawn Phenomenon & Somogyi Effect?

Table 2. Steps to take to avoid the Dawn Phenomenon & Somogyi Effect.


Consider A Great Blood Sugar Meter

OneTouch glucometers are a great option for you to practice self-monitoring blood glucose. Below are some of its features. If you want a high-tech multifunctional glucometer – go for the OneTouch Ultra Plus Flex meter. If you wish for a functional glucometer – go for the OneTouch Select Simple meter.

Tired of recording down your reading manually on a book? With this app, blood sugar level recording is automated. It can turn data into informative analyses which can help you learn how to manage your diabetes. 

OneTouch Promotion – From 10 Aug 2021 till 1 Jan 2022, purchase 1 set of  OneTouch Ultra Plus Flex Kit Blood Glucose Starter Kit + Ultra Strip 50s and get an instant RM30 OFF. 

Blood glucose meters such as OneTouch Select Simple and OneTouch Ultra Plus Flex help to make tracking your blood sugar quick and easy. The OneTouch Ultra Plus Flex meter requires only a tiny drop of blood for a reading. It has a large screen which allows easy reading of the blood sugar levels. The bluetooth technology enables the meter to be synced to your mobile phone and have all the blood sugar records easily accessible to the user to detect and reflect incidences of low sugar levels.  


Takeaway: It is Important To Self-Monitor!

Conditions such as the Dawn Phenomenon and Somogyi effect can only be detected via monitoring one’s blood sugar levels. It is vital that a diabetic person has a glucometer and uses it smartly. If you do have any questions related to diabetes, do approach your nearest outlet or message us on Facebook to find out more.



  1. Type 1 diabetic girl. Dr Poonam Jadhav. (Web accessed September 2021) Web link: https://poonamjadhavt1d.com/2019/12/03/dawn-phenomenon/
  2. Brijesh, M., 2015. Somogyi Effect in a Patient of Type 2 Diabetes Mellitus. Journal of Diabetes & Metabolism, [online] 06(02), pp.1-2. Available at: <https://www.longdom.org/open-access/somogyi-effect-in-a-patient-of-type-diabetes-mellitus-2155-6156.1000493.pdf> [Accessed 31 July 2021].
  3. ADA. 2021. High Morning Blood Sugars | [online] Available at: <https://www.diabetes.org/diabetes/blood-sugar-management/high-morning-blood-sugars> [Accessed 31 July 2021].
  4. Reyhanoglu, G. and Rehman, A., 2021. Somogyi Phenomenon. [online] NCBI. Available at: <https://www.ncbi.nlm.nih.gov/books/NBK551525/> [Accessed 31 July 2021].
  5. MedicalNewsToday. 2021. Somogyi effect: What it is, symptoms, and the dawn phenomenon. [online] Available at: <https://www.medicalnewstoday.com/articles/317998#When-to-see-a-doctor> [Accessed 31 July 2021].
  6. Healthline. 2021. What Is the Somogyi Effect?. [online] Available at: <https://www.healthline.com/health/diabetes/what-is-the-somogyi-effect> [Accessed 31 July 2021].
  7. The Center For Diabetes & Endocrine Care. 2021. Which are the best bedtime snacks for diabetes?. [online] Available at: <https://diabetesendocare.com/which-are-the-best-bedtime-snacks-for-diabetes/> [Accessed 31 July 2021].
  8. Glycemic Targets: Standards of Medical Care in Diabetes. (2019) American Diabetes Association. 42(Supplement 1): S61-S70.
  9. Management of Type 2 Diabetes Mellitus (6th Edition). Ministry of Health Malaysia. (2020). Clinical Practice Guidelines.

A community awareness message brought to you by: