I was diagnosed with insulin resistance in the 1990s, and used the T2 med Avandia for 13 years. I had gained a lot of weight, but lost most of it by reducing my carb intake. My control was very good, with very few highs and lows. There was a warning about Avandia causing problems with some people's hearts, so I started taking Metformin about 10 months ago. My weight had stabilized while on Avandia, but I have lost an additional 15 pounds while on Metformin. I am only 8 pounds above my ideal weight now. All that is good, but my BG's are no longer stable.
I am experiencing more low BG's since adjusting to Met. The Met reduces the amount of glucagon produced by the liver, and I am thinking that reduction may explain my increased number of lows. My liver used to dump glucagon to compensate for a lack of carbs/glucose, and my BG would rise. It would sometimes do that while exercising if I had insufficient carbs beforehand. That is not happening now, so with smaller liver dumps, I am having lows. Many times I am not feeling the lows until I am <50. That is because I am having more lows than ever before, and my body is adjusting to lower BG's. On a good day I can feel the lows when in the low 70s, and other times not until the low 50s. It may have to do with how fast my BG is dropping. A slow drop creeps up on me, and is harder to detect. Because of the increased number of lows my standard deviation has increased. I have adjusted to lows so much that I can easily handle lows in the 40s, and even the 30s, without ever needing assistance. There have been no lows less than the low 30s. There is no consistent pattern in my BGs, and adjusting my basals helps very little. Lows don't scare me now, but I am not sure that is a good thing. My A1c has been less than 6.0 for almost 10 years, except for a 6.1 in late 2007. That is good, but the irregularity of my BG's is of great concern to me. I may be becoming hypo unaware.
I am not having many highs, except when I hit scar tissue. I wish scar tissue was visible, but it isn't.
Overall, I like Metformin, and I am not sure that it is the cause of my having more lows. There is no other change in my diabetes management or my everyday life, so that makes me suspect the Met has something to do with this. What do you Met users think? Am I the only T1 Met user here?
I am not a Met user; I maybe totally off with my thought process ...but would the lows not be happening, if you stop using Metformin ( under Doctor's guidance ) ( or use less) , due to your weight loss ??
Hi Nel, that is a good suggestion. Some people on Met lose weight and then no longer need Met. I lost weight and cut my Met dosage in half using a pill cutter. Then my insulin resistance increased and i started having highs. It seems I have to take the full dosage. I could have increased my insulin dosages, but then I would have started gaining weight. The more insulin I use, the more weight I gain. I am currently using 34 units of Humalog per day (basal + bolus). It does not work well for me to go higher than 34 units per day.
Seems to me you're in sort of a damned if you do/damned if you don't situation. It's well known that the way metformin works is by decreasing liver production of glucose, and that may be because it reduces the liver's sensitivity to glucagon. Hence, your pancreas may well be producing glucagon in response to your lows, but your liver isn't responding to it (My theory only).
Also, did you know that someone (I don't remember who) is doing a study on using metformin in Type 1's? I saw it on Facebook, and Doris Dickerson (?) responded that it was nuts, because it would interfere with glucagon response to lows.
Anyway, the only way I know of to fight weight gain is to eat more protein and fiber, and reduce fat and carbs. The protein and fiber keep you feeling full for longer, and you just eat less. There are some of us (including me!) who just can't eat large portions and expect to stay slim. You may need to eat smaller meals more frequently in order to maintain some degree of equilibrium in your BGs.
Seems like you got the worst of both worlds, and the best, too, because in spite of the problems, you're still here with us! :-)
Richard, I'm far too new to this to be of much help, but you might consider changing the time of day that you take the Metformin, or spreading the Met out during the day. If you take, say, 2 500 mg. tablets now, you could see what happens if you cut them in half and take them at 6-hour intervals instead of taking 1000mg all at once.
As for increased insulin and gaining weight, Dr. Bernstein says that someone on a low carb diet who is gaining weight because of insulin or because they're near their ideal weight should reduce their protein intake at one meal by 30%. Keep that 30% reduction at the same meal--say, lunch--for a few days and see what happens. If you don't lose the weight, try reducing protein by the same amount at another meal--like breakfast--in addition to the 30% reduction at lunch. I know this works very well for some people.
I know that by now, we can probably count you as a veteran, but losing 15 lbs and starting metformin can markedly decrease your insulin needs.
Now, as to glucagon. Glucagon is produced by your alpha cells in your pancreas and are part of the system that tells your liver to produce blood sugar. Your liver produces blood sugar when your glucagon levels go high AND your insulin goes low. This is the counterregulation signals that help the hapless non-diabetics. Most diabetics on insulin take enough basal insulin that this natural counterregulation mechanism is overriden. It just doesn't work and that is why we have these risks of lows.
But as it turns out, glucagon is not the only signal that that tells the liver to produce blood sugar. Things like cortisol (stress hormone) or growth hormone (drives DP) also cause a production of blood sugar. And most importantly, in your brain, the hypothalmus controls the rate of background blood sugar produced by your liver and signals your liver with yet another method (Katp). So it is all very complicated.
That being said, metformin does suppress the production of blood sugar by the liver. I believe it does so by messing with how your liver recieves those signals (primarily Katp). The normal background blood sugar production is the target of our basal insulins. If metformin reduces the production of the background blood sugar level, it will reduce your basal needs. You should have observed this as you raised and lowered your metformin medication levels.
So what I suspect may have happened is that you are more "brittle" with the metformin (than you were with Avandia). Avandia improves insulin resistance but doesn't help in the other ways that Metformin does (it suppresses blood sugar production from your liver, increases bodyfat utilization and decreases the absorption of carbs in digestion). Before (with Avandia) you got mostly improved tolerance of carbs and maybe a little reduction in basal needs. Now (with Met), you still get the improved tolerance of carbs but you may have a bigger reduction in basal needs. Before, if you had a slight overbolus, it had a more modest affect against your basal and you may not have gone low. Now, any overbolus can be more significant compared to a your basal and may cause lows. This may be occuring on the tail of the bolus, 3-5 hours after a meal. Is this what is happening? Is there any pattern to the lows?
Yes, the lows are occurring 3-5 hours after lunch and dinner, but now after breakfast. I tend to run somewhat higher BGs in the early morning. My insulin:carb ratios on Avandia were 4, 6 and 7. On Met they are 5, 8 and 10. My insulin sensitivity has definitely increased. I am going to do extensive basal testing this week. That may correct my problem, but the lack of a consistent pattern may make it difficult. I wish I could use a CGM, it sure would help. I used the Dexcom for 8 months last year, but now my CGM is no longer covered by insurance. It is way too expensive for me, out of pocket.
Thanks Natalie, I have had very good control for many years. That makes a little problem like this one seem more troublesome to me than it would to so many other T1D's. I never stress over this kind of thing. It is a challenge and a game, and I always win in one way or another. I was just looking for shortcuts to save me some time. Extensive basal testing will probably solve the problem.
It would be perfect to have CGM and see exactly what is happening. Perhaps you could nudge your ratios up a bit and trade off going a little higher after meals and reducing the lows. But as you note, the lack of a consistent pattern can really make things difficult. Sometimes, it just helps to experiment.
I too started out on metformin, back in the early 80's. It is probably one of the oldest medications out there. I am happy that you lost the weight. In my journey I have also lost a significant amount of weight and am within 10 lbs of my so called ideal weight and height. I am 10 years younger than you, but have the energy of someone who is half my age. Over 30 years I have found out that losing weight and changing my diet has had a significant change to my management of this disease. When I lost those extra pounds I still could not get away from the lows you described, but I did adjust to the changes as time went by. You mentioned that your A1C is in the low 6's and that is very good. As a long term diabetic I am amazed by all the changes.
Time was long ago you didn't have the tools we have today. I feel fortunate. The last ten years I have been on insulin, which is not too bad. The ol' pancreas just gave out and I can accept that. I am still getting lows, but I feel them before I get into trouble. I always carry gtabs with me. Recently I went on an insulin pump with CGM and that darn thing requires a lot of attention. It does however give me a rather steady flat line during the day.
I also have lots of scar tissue, but has not been a problem for me yet. Most of it is from the labs when they draw blood from me. I rotate sites for iv's on a very regular basis. So far, so good.
Your concern about Metformin is reasonable. Although I do not use it anymore, I think it is a valid treatment for diabetes. Especially for T2's. I don't understand why you are taking Metformin for T1. T1s do not have any insulin. I suggest (not advise) that you talk to the doc about your concerns about this drug and maybe change to something more current. Maybe insulin like Lantis or Levamir may give you more control over 24 hrs.
Most important is to test your blood several times a day. Especially 2 hrs after a meal. You already know that. I know it is hard to keep that "perfect BG at 100". In my view the blood glucose is like the temperature outside - it goes up and down all the time. I accept that. The best thing is to keep the deviation from normal as small as you can.
I hope this post helps. Please feel free to come in here to learn and join a bunch of us who will put a hand on your shoulder.
I don't think metformin causes kidney damage. Tylenol can cause kidney damage, but I've never heard anything about metformin mentioned. Now if you have kidney failure, you should be careful about the use of metformin because it won't be properly cleared from your body (but the same caution applies to Tylenol).
I have read several type 1 diabetics saying they are taking Metformin, and almost all of them are being helped by it. Type 1 diabetics can have insulin resistance too, and Meformin has done very well at controlling mine. There are some people who have very bad side effects from Metformin, but I do not think kidney damage is one of them.
The fact that Type 1's can have insulin resistance and Type 2's can have antibodies is why some scientists are beginning to look at diabetes as a spectrum rather than an either/or.
I don't know as much about antibodies, but I do know that insulin resistance occurs on a spectrum among non-diabetics, and is only partly related to weight, so why should diabetics be any different? If metformin, or some of the other drugs that work on gut hormones help you control your BGs, just being a T1 shouldn't disqualify you from using them. While drugs like the sulfonylureas, that stimulate beta cells, obviously won't work, some of the newer drugs, such as the DPP-4 inhibitors, could very well be useful.
