Welcome to another edition of our weekly Ask D'Mine column! But before we get started, we want to wish Amy a very Happy Birthday today!

We hope Amy has a fabulous and relaxing day with her family and friends. She deserves it!

And now, back to our regularly scheduled programming...


Too much insulin, too little insulin... Goldilocks had nothing on PWDs! This week, our host Wil Dubois, diabetes author and community educator and also a veteran type 1 himself, helps two readers figure out how to get their insulin doses just right.

{Need help navigating life with diabetes? Email us at AskDMine@diabetesmine.com}

Robin from New Jersey, type 1, writes: I'm a recently diagnosed Type 1, and my insulin requirements seem to change pretty often. Even when I eat the same healthy meals and have roughly the same activity level, my BGs suddenly start jumping higher for a few days. And then they'll drop. I've had various changes in my dosing, but I feel like I'm chasing the wind trying to get an MDI plan that works. I can't change my bolus calcs or basal dose every time I have one high or low day, but I hate having high BGs for hours on end. If I'm careful about insulin already on board, how often can I give a small correction dose of fast-acting insulin to get back in line?

PS—I LOVE your Q&A column. Your good humor and down-to-earth approach really make a tangible difference for me and many others!

Wil@Ask D'Mine answers: Thank you for the vote of confidence on the column! Much appreciated. Ahem...

So what we are talking about here is strategic stacking. Or maybe it's tactical stacking. Hmmmm.... Fun question.

OK, so in a test tube, our modern fast-acting insulins last up to six hours. In most folks, the realistic effect tapers off at the four hour point, but that said, a lot of endos prefer to use a three-hour duration of action when figuring these things out. At any rate, the smart money says the insulin will last between three and four hours. The common wisdom invested in the smart money says not to bolus more than every four hours to avoid a stack-and-crash.

But let's think about this for a moment.

The whole "avoid stacking" thing assumes that you've actually taken enough insulin to get the job done, but the job just isn't done yet. It's an approach that counsels patience. But what if you didn't take enough insulin? Then it wouldn't matter how long you wait, you'll still need to add more insulin. So the question becomes, how do you know when it's safe to assume you don't have enough insulin on board to finish the job?

My vote: two hours.

For me, I find that I do get a solid four hours out of a shot of fast-acting, based on the fact I sometimes get hypos right around the four-hour mark. Hey, if the insulin had worn off at three hours, it wouldn't be able to force my head underwater an hour later, right? So I think if, half way through the insulin's run at two hours, you're not yet half way to where you want to be, you can—and should—take some more insulin.

In short, you need to do some math, and if the job is less than half done at two hours, get some more workers on the case!

Sooooo...practice time! Let's pretend you were at 300 when you corrected, and want to be at 100. If two hours downstream you're at 200, should you take more insulin? No! You're half way through the insulin's duration of action and you're half way to your destination. Things are going perfectly! (Going from 300 to 200 is a one-hundred point drop and, in a perfect world, you'd expect to be half-way home in two hours.)

If you are, say, at 250, you could go ahead a take a sip of insulin. Not as much as you would take for 150 points high—you've still got insulin in play for 100 points worth of drop—but you could take some more for the extra 50 points that you're still above target.

Of course, in two more hours, your original correction dose for the 300 is gone, but you still have half the insulin you took for the 50 points over target. If you're not down to 125 at this point you can take a third correction (remembering, of course, that you have half a 50-point correction still in the pipeline).

And if you're going to do much of this, may I suggest a notebook and pen?

Now, word of warning before all the endos and techno freaks start flaming me. The system I just advocated for suggests a linear duration and method of action for the insulin in your bod, which it isn't. It's really curvilinear. That is to say the insulin in your body isn't like sand flowing through an hour glass. Insulin takes a little while to ramp up in your body, and at peak action it has more punch than it does towards the tail end. So using a straight line approach, in theory, under-estimates the first hour of insulin and over-estimates the last hour. But as we are playing the averages anyway, and because diabetes and blood sugar have more in common with chaos theory than normal math, I think you'll find my approach not only "good enough," but practical and usable without needing an advanced degree in mathematics.


Christy from Missouri, type ??, writes: I was hospitalized in the middle of November. The doctor diagnosed me as type 2 and put me on 500mg of Metformin twice a day. He told me I had ketones in my blood and urine but was not acidotic. Later, in December, I began seeing a nurse practitioner. She did a metabolic panel and my A1C came back 14.3. She told me I was type 1, and within a few visits I was shooting 20 units of Lantus before bed, and 4 units of Novolog before each meal. Plus the metformin twice a day. The insulin, while very effective in controlling my postprandial spikes, presented a whole new set of challenges. I quickly learned that if I didn't have enough carbs in my meal, I would go hypo. I would shake, then sweat, followed by a headache. I feel like I'm a walking experiment. I don't know what to make of all of this. If I respond so strongly to the insulin, am I a type 2 like the doctor said, or a type 1 as the nurse told me?

Wil@Ask D'Mine answers: One if by land, two if by sea... Sorting out who's a type 1 and who's a type 2 is not as easy as you would think it would be. Virtually every test in our arsenal is subject to false positives or false negatives under some circumstances.

So I'm not sure either which type you are. Type 2s generally don't have ketones, but they can. Type 2s are generally more insulin resistant, but not always. Both type 2s and type 1s can respond to metformin. What a mess! But you know what?

It really doesn't frickin' matter.

And that's because what kind of diabetes you have is not likely to change how you, Christy Q. Mystery Diabetic, will control this illness. Here's why: first we know that metformin, all by its little lonesome, did a miserable job of controlling your diabetes, leaving you at dialysis-friendly A1C level of 14.3. We also know that most oral meds will only lower A1C by one point or less. To get you from 14.3 to 6.3 on oral meds alone would require at least eight different pills. Screw that. Better to break out the insulin.

Insulin, wonderful insulin, is infinitely scalable. You use as little or as much as you need to get the job done. But you should be taking.

Novolog to cover your food, not taking food to cover your Novolog. I was disturbed to hear you have to eat "enough carbs" in your meals to keep from going low.

I think this is because you're using flat-rate dosing, which isn't the best way to use the med. A flat dose of Novolog requires a flat dose of food. Flat-rate dosing is simple, but it's likely to give too much insulin for some meals, and too little insulin for others. Your medical team should take some time to help you figure out your insulin-to-carb ratio. This will let you vary the size of your mealtime shot depending on the size of your meal. Some meals might need only two units, others might need ten. You'll also need to learn how to count carbs so in order to determine the right amount of insulin to take.

As you do seem pretty insulin sensitive based on your Lantus and Novolog volume, you should also talk to your medical team about whether or not you still need the metformin at all.

Hopefully some med changes will convert you from a walking experiment to a walking success story, even if still a mysterious one.

This is not a medical advice column. We are PWDs freely and openly sharing the wisdom of our collected experiences — our been-there-done-that knowledge from the trenches. But we are not MDs, RNs, NPs, PAs, CDEs, or partridges in pear trees. Bottom line: we are only a small part of your total prescription. You still need the professional advice, treatment, and care of a licensed medical professional.

Disclaimer: Content created by the Diabetes Mine team. For more details click here.


This content is created for Diabetes Mine, a consumer health blog focused on the diabetes community. The content is not medically reviewed and doesn't adhere to Healthline's editorial guidelines. For more information about Healthline's partnership with Diabetes Mine, please click here.