Sugar running high again. No apparent reason

I’ve had a really good run with my sugar levels for the last few months. Generally between 70 (4mmol) - 180 (10 mmol) most of the time - the best control I have had for a very long time.

But the past week, it has been shocking. My sugars have been very hard to control, particularly during lunch and before midnight. Even increasing my insulin bolus by 3-4 units more than what I usually take and temp basal increase of 150% doesn’t budge it. I’m still above 180 (10 mmol) for hours and it won’t come down despite frequent correction boluses.

This has happened before last year… and then all of a sudden it went back to normal. I was like that for about a month or so.

I don’t know whats causing these annoying highs, i’ve changed infusion sets, changed insulin and still the same. My period is about to come and I read this could cause highs… but if this was the case, why hasnt it been the same in previous months?

What’s worst is my dexcom alarms for some reason has stopped alarming when its supposed to. I set an overnight alarm between 11pm to 7am. I was above my threshold around 11:30pm but i wasn’t woken by the alarm until like 2am at which point it was already through the roof. I tried to uninstall and install again, hopefully it is better tonight and alarms properly.

Anybody able to help explain why these highs? Hormones maybe but how to even prove it is that?

What’s your COVID-19 status?

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Don’t think I have covid, literally haven’t been out of the house for a while. I’m tripled vaxed and no symptoms. When it happened last year, I suspected it was to do with my thyroids and I was getting palpitations. Could explain why when i got it under control my sugars went back to normal. But this time round, no palpitations and no signs of thyroid playing up. May be time to get a blood test.

Are people reporting unexplained highs when they have covid?

The only reason I ask is due to the many reports of asymptomatic covid. Any significant infection, bacterial or viral, will drive up blood sugar levels and make them stubborn to correct.

Have you delivered any correction doses via syringe? Have you changed infusion sites more than once?

As a man, I don’t have any experience with that but have read many comments from women here talking about the blood sugar challenge of managing monthly cycles. I believe that there are apps that help with this.

Once or twice a year, I go through a situation where I need a significant increase in insulin only to see my insulin need back off and return to my former levels. I have not gotten to the bottom of that riddle but I give my body more insulin when it asks for it and reduce the insulin when it doesn’t want it any more.

Congratulations on this! It bodes well that you will be able to return to this level of control.

These curve-ball riddles are part and parcel of dosing insulin for me. I’ve found that flexibility is key here. Diabetes is not a set-it-and-forget disease; it is dynamic and if you don’t change with it, it will make you miserable.

Good luck!


Thanks terry.

Yes multiple times. I also started a new box of insulin around the same time. I can’t remember whether it happened before or after starting it. But with manual injections I do see come down most of the time so I didn’t think it was insulin.

I already changed the site twice too and even swapped out the cartridge.

I do wonder whether there is something going on in my body like a infection like you say that is causing this, and the stubborn sugar is just it’s way of dealing with it but I don’t feel unwell at all. My body reacted badly to the covid shots, felt like I was hit by a bus and I was completely bed ridden for 2 days, but my last shot was in December and these sugars only started playing up in the last week or so.

The only other thing I can think of is my menstrual cycle has been a bit off in the last 3 months. So perhaps it is hormone related. Can’t be onset of menopause can it, I’m only 40.

I’ve been battling a rising sugar for the last two hours. Even going more aggressive than what I usually give, it’s still on the rise. I must have injected 3 units of correction bolus in the last two hours and still, no sign of it coming down. I hope I don’t end up crashing at 3am.

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Do you have access to a covid quick test? The only time that I’ve ever found my insulin to be bad was when I froze it in the refrigerator.

Have you considered missing a meal or two and see what happens? I’ve found fasting a reliable tactic to rein in stubborn blood sugar levels. It’s effect is slow but it gradually increases insulin sensitivity for me.


Quite possibly not at all helpful but I sometime resort to exercise to bring down a stubborn high. With insulin on board, often it takes only 10-15 minutes on treadmill or bike.

I don’t have hormonal cycles to account for it, but sometimes I’ll see a big increase in amount of insulin I need. Even with no real change in any other obvious parameters.


I have 2 periods of 7-10 days each year when BG control is real tough. In the Spring when the weather shifts from cold to warm and then again in the Fall when the weather shifts from warm to cold outdoor temperatures.


I have been having a similar situation.
I believe I have been over using my infusion sets and it stops absorbing.
To test this out, I started taking once a day injections of Lantus along with my pump. I’m taking 15 units in the morning.

This drops my basal needs by more than half, but I didn’t need to adjust it as my pump does that for me. My total insulin is still about the same.

I was finding my glucose shooting up and extra insulin was just overwhelming the site. Now it hardly happens at all.

I’ve accepted that anything more than 40 units a day will cause me absorption issues. With my 15 units of Lantus, my pump is pumping 35 units on average.


Did you switch to a new vial of insulin?
Or just fill new cartridge from vial aready started?

Both, new infusion set new vial
And new cartridge

The only thing I haven’t tried is a new box of insulin. Each box has 5, I’ve gone through insulin from the same box.

Each box has the same batch number so i didn’t think it would make a difference

I’m 44 and have had the same issues for about a year. I am putting it down to peri-menopause, but have no answers I’m afraid - i just firefight, as you can bet that by the time i make some changes to my basal it will all turn around again and go back to normal. I feel your frustration.

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I agree, fasting can be useful as a reset tool.

This is true for me too.

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My twice a year challenge revolve around Standard and Daylight savings time clock shifts.

My circadian rhythms take far longer to adjust to clock changes than they did when I was younger.

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Don’t most of us have these weird episodes of either having constant unexplainable lows, or highs? I get them maybe once a year. Sometimes they last for a few days, Sometimes they happen for just one day. I happened to see my doctor (PCP/endo) a few days after one of these episodes and his take was, “Diabetes is kind of a weird disease, so when everything is weird, I think one weird day is pretty normal.” Love his sense of humor. His advice was to test a lot to make sure I’m not too low or too high, but other than that, an off day, or even several off days a few times a year isn’t going to hurt me in the grand scheme of things. It is, however, darn frustrating.

What’s even more frustrating is this one person in my life who, if I ever have a low when I’m with him, seems to think that if he just asks emough questions, he can “help” me figure out what8 happened so I can avoid lowd in the future. Lows don’t normally cause anger for me, personally, but the last time he started up with this stupidity when my bg had gone down to the 30s, I have to admit murder wasn’t far from my mind!


But it might be an interesting defense strategy :fearful:.


Haha, Mm1…I’ll keep that in mind for future occasions.

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We know there are so many possible factors that could cause “unexplained” lows. One of them (for me, at least) is having an infection. This usually throws off my BG control. As a TD1, of course I treat cuts/abrasions immediately and seriously, but I do sometimes get infections. When you experience such lows in the future, you might review if you could be having either an infection or some other sickness that is affecting your BG level.

A personal comment – you really want to avoid going down to the 30s. Not good for your body, including your brain. If your Endo and your insurance would support a continous glucose monitor, I highly recommend it. Mine is set to alert at 70, and I take action immediately. With modern technology, there is no reason to ever go below 50 and even that is avoidable these days.

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Jim10 -
Luckily, I rarely go that low, like maybe once every couple of years. I usually catch them in the 50’s or 60’s.

Because I’m very sensitive, even allergic, to many adhesives, I don’t want to get a CGM…just another site to worry about. I already have a couple of areas I can no longer use for my pump sites because my skin scarred from allergic reactions to the barrier tape (and I’ve tried several different kinds…the one I’m using now gives me the least trouble.)

Ironically, the person in my life who really doesn’t understand…it was partly his fault that I went that low, due to a whole bunch of stress from him, and running errands for him that he kept texting different info and asking me to go back into stores I’d already checked out of to get “just a couple more things.” I know he means well, but his Parkinson’s is so bad now that he has trouble thinking and planning. Wish I could do more for him, but not at the expense of me ending up in the hospital.

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