Tell us about your experiences with weight management. Take our survey!

caret icon Back to all discussions

Blood sugar reading spiking after waking up

I just started using Freestlyle Libre 3. Both days so far had a reading in the 90s upon waking up just before getting out of bed. After getting up, showering and getting ready for work but no eating, the reading went up around 50 points both days. Is this a CGM issue or is something else going on? I have been type 2 for around 15 years but have been negligent about checking my glucose levels for about two years.

  1. Hi That is interesting, though probably very frustrating for you. Do you take any morning medicatons that might cause an increase in your blood sugar after waking? Do you still have your old glucose meter? If so, maybe you could double check with finger pricks to ensure the results are the same as those from your Libre 3, or at least close. I wish I could be of more help. Hopefully, others will chime in here. Best wishes. - Lori (Team Member)

    1. Hello , My husband was going through this also. He was checking his blood sugar immediately upon waking. This was before eating or drinking anything. His healthcare team told him to test his blood sugar 2 hours after a meal, which is when his blood sugar returns to normal levels. Of course, we are all different. Have you been able to talk to your doctor? We would like to hear from you. Diane (Team Member)

      1. The dawn phenomenon, also known as the dawn effect, is a rise in blood sugar levels that usually occurs between 3 AM and 8 AM. It's common in people with diabetes or insulin resistance, and happens when the body releases hormones like cortisol and growth hormone, which signal the liver to produce more glucose. This glucose boost provides energy to help you wake up, but it can also lead to high blood sugar levels, also known as hyperglycemia.
        Some ways to prevent the dawn phenomenon include:
        Avoiding carbohydrates before bed
        Taking insulin before bed instead of earlier in the evening
        Asking your doctor about adjusting your insulin dose or other diabetes medications
        Using an insulin pump overnight
        To determine if you're experiencing the dawn phenomenon, you can test your blood sugar at different times over several nights: Right before bed, Between 2 AM and 4 AM, and First thing in the morning.
        You can also consider wearing a continuous glucose monitor to track your sugar levels throughout the day and night. If your blood sugar is normal or high between 2 AM and 3 AM, it's more likely that the dawn phenomenon is the cause. You can then take your results to your doctor to see if there's anything else that might be causing your high blood sugar levels.

        Hope this helps.

        1. great explanation! Thank you for sharing! - CJ (Team Member)

      2. Hi , I hope you are doing well. Have you been able figure out what was causing with the rising blood sugar numbers? Kristal shared some great information about dawn phenomenon. I also wanted to add a quick resource about this from T2D: - CJ (Team Member)

        Please read our rules before posting.