Trying out Metformin... Wow!


I agree, this has better effects for me than metformin. I could still get up very high, but often it would cap highs at about 14 mmol/L (250 mg/dl) that I’d otherwise be struggling to get down.

My most recent A1c came back at 6.8%, which is creeping a little higher than I’d like (I’d like to get back to 6.0-6.5%, the last three have been above that). So I’m going to be looking at ways to get back down a bit. I may give SGLT2 inhibitors another try, though for me side-effects hit within six weeks even at a 5 mg dose, so I don’t think that’s promising. I have wondered, though, if I could use them on a short-term basis in the week or two before my cycle, as that’s the time I’m most prone to stubborn highs and it can be hard to adjust basal exactly the right amount without then ending up low.


I take 2000mg via 4 pills, and I take two in the morning and two in the evening. I do not think taking it all at once would work as well for me. My endo had me splitting my dose in two once I went above 750mg, but I suspect it might be a reason to go to a higher dose in the first place after easing in in case of digestive effects for many folks (to 500mg bid), unless you’re just targeting overnight, in which case one dose would make sense. I suspect dosing several times a day might even be best, but I don’t think I’m likely to be well disciplined with that.


@Katers87, I feel, like @Chris, that this is an outstanding post! This thread is really excellent. Thanks so much for sharing your experiments!

FYI, here is an interesting 2017 article that compares therapeutic effects of Metformin (ie IR) vs Metformin XR:


I wanted to mention that almost hte same thing happened to me. I couldn’t tell if metformin was helping and wondered about stopping it. Then I missed a dose and, wow, battled high BGs the entire day. Every time I miss a dose, without question, it’ll be an entire day out of range. So it’s definitely doing something, and I’m actually more diligent about taking it than some of my other medications because of the very noticeable effect of missing a dose!


I’m going to be starting a trial if metformin
ER this week too… the amount of mealtime insulin I have to take just seems to keep rising forever upwards… to the point that much of the day my IC ratio is like 1:4 or so… although my doc doesn’t seem to take it seriously because my total daily doses are pretty much within spec for a non insulin resistant type 1… but finally I convinced him that I’m not as insulin sensitive as he seems to think and it’s worth a try. Am looking forward to it. Will make a thread too if there’s anything to see…


Starting tomorrow, I’m going to start splitting my metformin dose into a morning dose and evening dose of 1,000 mg each. I’ll be curious to see if it has any impact.

Also, I’m not sure if this is due to metformin, but I don’t remember seeing this prior to metformin. Does anyone get a drop in blood sugar every time they get up? In the morning, I frequently go low a half hour to an hour after waking up, even if I’ve spent most of the night high (though in that case, usually I end up taking a middle-of-the-night correction bolus, so I do have insulin on board). Today, the same thing happened after a nap lasting about an hour or an hour and a half (I had insulin on board for that nap, too, from a previous food bolus). Maybe it’s just a coincidence, but I couldn’t help wondering if it had anything to do with metformin.


I’m also curious! Let us know how it goes :slight_smile: I expect you might have to adjust your basal rates at multiple times during the day. Or not? Curious to see what happens.

I am more insulin sensitive when I’m active/awake, but I don’t have drops when I first wake up. Any decreases in bg levels are related to activity or insulin.

I only switched to evening metformin a little while ago though, maybe after a month I’ll see different patterns.


@Jen, I thought your daily dose was 1,000mg? If so, be careful about the possibility of digestive issues for the first 3-6 months :slight_smile:


Nope, I described my daily dose earlier in this thread:

So no worries about digestive issues. :slight_smile: That’s actually what seems to be different about Glumetza: it’s like extended-release metformin, but it’s broken down slightly differently such that it minimizes the risk of gastrointestinal side effects (at least that’s my understanding).

All I’m doing is taking my morning 2,000 mg dose and splitting it so that I’ll take 1,000 mg in the morning and 1,000 mg at night, now that I know that the 2,000 mg dose doesn’t last for 24 hours like I thought it did. I’ll be interested to see if more even coverage has any benefit to my blood sugar.


Quick update/conclusion:

The evening dose is still working much better for me. I’m not experiencing drops during the day. I’m responsive to insulin at night. I’m still surprised sometimes at how effective the insulin is now.

I’m experiencing some minor digestive discomfort, but nothing significant and nothing that would influence my decision to continue using Metformin.

I bumped my dose up 1 unit for the last week of my monthly cycle (which was needed in the prior 2 months as well). It looks like my overall monthly basal need patterns have remained similar since starting metformin- just 1 unit lower than usual throughout the whole month.

My muscles seem to ache a little more after hard workouts since I started Metformin. I don’t know if this related or not.

In my last post, I said I was watching for increased sensitivity to alcohol. I’m not really noticing this anymore. Must’ve been a fluke evening.

I think Metformin has been a very useful addition to my diabetes management, and I plan to continue using 500 mg/evening. If something new comes up, or I decide to stop/change my dose, then I’ll update this thread. :slight_smile:


You probably already mentioned it but are you using the metformin ER? Or the standard metformin?


I’m using the Metformin ER.


Yeah that’s what I’m getting too, supposed to start with 500 mg in pm for a couple weeks then go to 1000… not sure if that means 500 am and 500 pm or 1000 pm


Let us know how it goes. I hope it helps!


I only learned that some type 1s take Metformin recently! Why did you start taking it? Did you or your endo suggest it?


I started taking the Metformin Extended Release version almost a month ago (different than standard metformin). The first post of this thread is about a week after I’d started using it.

I suggested it to my endo. I’d read about other people with type 1 taking it. I had noticed that my insulin sensitivity was much lower in the evening, and it seemed like I had to take a lot more insulin to correct highs (if they corrected at all…). If I bumped up my basal, I’d end up with lows in the early morning.

I saw two options: try out metformin or switch to Levemir or Lantus. I decided to give Metformin a try first. My doctor initially said that he thought it would just make me drop low during the day. He thought that it wouldn’t help, but he said he was willing to let me try it out at 500 mg each day taken in the morning.

I had some success in the evenings even with a morning dose. I did have some lows at first, and so I decreased my basal. Then I started having lows when I was active. I walk a lot on a day-to-day basis, so this was problematic for me. Eventually, as described in this thread, I switched to the evening because I read about Metformin’s action curve (see earlier post).

I haven’t followed up with my doctor, but I plan to tell him that the time Metformin is taken matters quite a lot. It’s helping me a lot with my insulin sensitivity in the evening, and I plan to continue using it.

@michel’s post also goes over some benefits of Metformin XR outside of insulin sensitivity:


I’m also a T1 taking Metformin ER, and I started it on recommendation from my endo (who is a very open-minded, forward-thinking one—I’m very lucky to have him). He noted that my insulin requirements had crept up and I’d gained some weight on my belly (a sign of insulin resistance), which is unusual for me, since I’m typically more of a mix of an hourglass/pear shape. It was a great rec, and now I take 2000mg a day (1000mg bid), and I lost the weight I gained and dropped my insulin dose significantly. It also greatly reduced if not eliminated my dawn phenomenon.


Are you seeing the insulin doses more reduced with mealtime insulin / corrections or moreso on the basal side?

My basal dose isn’t real high but I have to take a lot with meals… that’s where I’m hoping to increase my sensitivity


More with basal, but my ICR and correction factor in the morning in particular also went down significantly—I am far more insulin sensitive in the morning than I used to be. To be honest though, I can’t say for sure about mealtimes because my ICR the rest of the day didn’t change dramatically, but my A1c improved considerably, so it could be that it went down some because it wasn’t actually high enough before.


I thought I’d update even though it’s only been one day since I split my dose. (I’m also Type 1, childhood onset, though I’m also overweight so likely do have a degree of insulin resistance.)

My overnight numbers since starting metformin a year and a half or so ago has been that I get a rise in the evening and just after going to bed, and if I don’t correct it I stay high all night. If I do correct it, I very often end up going low. If I try correcting it before bed, I often end up low.

After learning in this thread that my Glumetza (like extended-release metformin) does not actually last 24 hours, I decided to split my morning dose into a morning and evening dose.

It’s only one night, but last night was incredibly flat for me. I went to bed at around 8 mmol/L, took a cautious 0.5 unit correction, and woke up around 7 mmol/L. It was a flat line, rather than a sharp rise followed by a fall, like a mountain peak.

I’m now wondering if the evening/overnight rise was actually the morning dose of metformin wearing off, at least somewhat, and my liver going into overdrive. Though I did find since starting metformin that the nasty dawn phenomenon I’d had for years basically went away, so I do think metformin has some effect for 24 hours, just not full effect. It’s only one night, but the split dose did seem to hold things much more steady.

We’ll see what tonight brings. I should also note that I’m in my hormonal calm phase, so things may also change in a week or two when that phase ends.