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Type 1.5 Insulin and Metformin and hypo after 4-5 hours

AnnieRL

Member
Messages
7
Type of diabetes
Type 3
Treatment type
Insulin
Hi, I’ve had a search and can’t find anything on this so hope you don’t mind me starting a new topic.
13 years ago most of my pancreas was removed and since then have been on basal 1 time a day, bolus 3 times per day. I have a Freestyle Libre 2 sensor.
A couple of months ago my Endocrinologist suggested adding in Metformin. Initially 1x500mg per day increasing to 3x day.
Since starting the Metformin around 4-5 hours after taking the Metformin and injecting I have a very dramatic crash usually resulting in a hypo. This happens consistently. Now I understand that Metformin does not cause hypos and have discussed it a few times with diabetes nurses - they just tell me to reduce insulin, which I have done. HOWEVER I can’t reduce it enough to stop the “plunge” because then I would be getting super highs after eating. A catch 22 situation.
The diabetes nurses just say “your figures are really good” but they are just looking at my averages, not the dramatic plunge 4-5 hours after injecting.
Am beginning to wonder if I have a bad reaction to the Metformin or is this normal - anyone have any thoughts on this please? Don’t have Endo appointment till July. Thank you.
 
Hi @AnnieRL ,

Welcome to the forum.

What insulins are you prescribed?
 
AnnieRL said:
Lantus and NovoRapid
Click to expand...
When do you take the lantus?
(I do lantus.)

I have noticed Novorapid for me can have a lick in the tail around the 5 hour mark? Which can cause a low.

I don't do metformin.
 
I used to take Lantus in the morning but since starting the Metformin I was advised to take it in the evening. Maybe it might be an idea to return to morning for Lantus (nurses weren’t keen on this). I do try and time meals to catch the plunge but tend to either under or over dose with insulin as it’s now hard to calculate. Darn Metformin has messed everything up - never had this problem before. Feels like I’m back at square one again
 

What I know about metformin is it increases insulin sensitivity (allegedly.) & stops a liver dump?

But with insulin alone. It can be like “spinning plates.” I’d say your insulin is the “hypo culprit.” But which one?

You could look at basal testing to check your Lantus profile is behaving before experimenting with timing of the novo?

How To Successfully Test Your Basal Rate

Are you looking for basal rate information and testing instructions? Perfect! You're in the right place!
www.mysugr.com

But with metformin in the mix. I’m not sure how this could play out? (My understanding it is recommended to take met with food??)

When is your next appointment with your diabetic team?
 
Thank you Jaylee, hadn’t heard about basal rate testing - there have been many developments since 2009 when I lost most of my pancreas. This is fascinating.

It is recommended to take Metformin with food but that seems to be mainly because of side effects which I don’t seem to get. I am someone whose BSL rises with exercise.

I can contact the nurses on the hospital diabetic team at any time, they are very good at following up although as I mentioned before they tend to only look at the daily patterns. It’s the 4-5 hour after insulin dramatic drop that is my main concern, if it’s something “normal”then I need to learn to work with it. My next appointment with the Endocrinologist is in July. I’ve recently moved to Scotland and this is a new team - have been very impressed with their thoroughness after spending years being managed/or not by GPs.
Being straight type 1 or 2 is obviously easier as you then fit more into a box.
Edit: Lantus has been reduced from 42 to 36 and NovoRapid from 16 to 10 units (except breakfast which is 12). Done gradually over a couple of months.
 

Oddly, lately. I seem to be more insulin sensitive. My basal on the whole seems OK. But the Norvorapid insulin to carb ratio needed a change. But there still can be a drop at the five hour mark after food?

But that’s just me as a type one. Im not a fan of being held to ransom eating to the insulin. Spent years doing it as a kid on fixed porcine insulin. “Oh, you need to snack here.” Says a nurse…. The dose & working profile should compliment our diet. The basal dose should keep things level when no fast acting is onboard? Easier said than done.

Best wishes.
 
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Hi @AnnieRL Welcome to the forum

Are you carb counting and adjusting your Novorapid accordingly, or are you on fixed amounts each day, of 12, 10, 10 irrespective of what you eat?
 
Hopeful34 said:
Hi @AnnieRL Welcome to the forum

Are you carb counting and adjusting your Novorapid accordingly, or are you on fixed amounts each day, of 12, 10, 10 irrespective of what you eat?
Click to expand...
Hi Hopeful, thank you for replying, I WAS carb counting, after a fashion as I’ve never been trained. After a while I’d come to know how much insulin was needed for meals (I do check the carbs in what I’m eating). Since the addition of the Metformin I don’t know how to calculate doses as my numbers are all over the place. ie sometimes before a meal my BSL might be 5 ish or it might be 8. The nurses seem to want me to have fairly set amounts (as mentioned above) and only modify them after 2 or 3 days of similar numbers.
On the whole I eat fairly low carb, with occasional lapses . I am mostly plant based but eat fish. Since getting the Libre sensor now know that bread, oats, pasta and rice (all brown and wholegrain bread) cause me to spike and plunge quite dramatically so have been trying to cut down on these - very difficult as they are the simplest meals to prepare.
Sorry for my rambling
 
Hi @AnnieRL let me see if I am understanding correctly.

You are diabetic after damage to your pancreas so presumably T3C??? Do you have any idea how much insulin your pancreas is still producing? (Some T3cs have to take creon because the pancreas does a lot more than just produce insulin.)

In theory, in someone with a fully working pancreas, as far as blood sugar is concerned there is a feedback loop with insulin and glucagon. Basically, if your bg goes high you produce more insulin, while if it goes low then your pancreas stops producing insulin and produces glucagon to tell the liver to produce glycogen (sugar).

Insulin and Glucagon: How Do They Work?

Insulin and glucagon are hormones that help regulate the blood sugar (glucose) levels in your body. Find out how they work together.
www.healthline.com

Some T3cs have horrendous problems with hypos if their pancreases no longer produce (enough) glucagon.

As far as metformin goes, as well as making you more sensitive to insulin, it inhibits the liver's production of glycogen, so although it is not regarded as a drug that causes hypoglycemia directly, it can cause issues when combined with drugs that do cause hypos, such as insulin...

Now, I am not saying that this is something that is relevant to you, but it might be worth asking your team about.
 
I have had the same problem with hypos 4-5 hours after eating and suspect that it might be related to what @EllieM suggested regarding glucagon, but I don’t know. I’m not sure what else it could be though… novarapid has well and truly worn off at the 6 hour mark unless I’m a freak (which is possible). I have only about 1/4 of my pancreas left so it stands to reason that if I’ve lost 75% of my beta cells, I‘ve also lost an equivalent amount of alpha cells. Nobody has brought this up though; not endo, not diabetic nurse, not GP. Just a constant juggling act with basal and rapid insulin, and still closely watching my diet. I’ve now managed 2 weeks 100% TIR but it wasn’t easy and I’m eating fairly low carb after discussing with my DN because taking more novorapid to cover the carbs just seems to make me go hypo 4-6 hours later.

Edit: my basal dose seems correct. I can fast for 24 hours with only lantus on board and my BSL will stay a steady/hover around 6. It’s only when food and novorapid enter the mix that things get complicated for me. I haven’t changed my diet a whole heap really, just incremental changes changing an ingredient here and there (e.g. almond milk instead of dairy milk) to reduce carbs a little bit at a time. But it’s not just carbs. I need carbs to stop hypos, but I also need novorapid to stop going crazy high no matter how much I reduce carbs and corresponding insulin reduction. It was happening after novorapid should have worn off anyway so… tricky
 
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Oh a sibling from another mother Darn pancreas! Was beginning to think I was crazy.

Just had a sleepless night with alarm going off repeatedly

My medical care continuity has suffered because I have moved around quite a bit, even changing countries. I was under a hepatobiliary team for first 3 years (in Australia) but after that things were left to general practitioners. It was only when I moved to Scotland (from England) that I was referred to an endocrinologist.

I was taking Creon for the first couple of years but found things were working ok without them so now don’t.

Am going to read through some of the posts on the T3C forum. Hope this makes sense - my brain is all over the place at present
 

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Thank you Ellie, just saw this as didn’t get notification. That makes sense. No one has diagnosed me as 3C. My current Endo says tests show I am producing some insulin which is why she suggested adding in Metformin. Pretty sure haven’t had a c-peptide as no fasting beforehand. Am going to ask for copies of all tests (which I usually do but forgot in this instance). I will pass on what you have said to her.
 
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