Issue with T:slim for type 2 with high insulin use

The T:slim has a bolus limit of 25 units, after that is delivered you can have the option of 25 more for a total of 50 units but that's it.

Here is an example of how the problem effects me. I am using an insulin to carb ratio of 1:1.5. For breakfast if I eat a bagel (50 carbs) along with an average size apple (38 carbs) and 8oz of Milk (13 carbs) that comes to a total of 101 carbs so with my ratio I would need 67 units of insulin. The T:slim pump will not allow this much for a bolus. I thought about delaying a bolus but to deliver the initial 50 units would take close to 10 minutes and a delayed bolus has to wait a minimum of 15 minutes before it will begin. This means that the total bolus would take up to 25-30 minutes. This seems to be unacceptable not to mention it would be a big pain in the a$$ to have to do this every time I need to bolus more that 50 units.

I talked to Tandem and they told me that the FDA has set this limit and they cannot change the programming of a pump to accommodate my issue.

I have only had the pump for a few days now and did not see this coming.

I have been out of commission with a major foot problem that had me in a cast for 14 months and now I am looking at surgery in spring. In the mean time I have a lot of pain. I know more exerciser would help my insulin usage but it will be another year before I might be back on my feet (pun intended). Of course loosing weight will help too but find it hard being off my feet.

I Just needed to share my frustration but I'm sure things will work out soon. Low card diet, here I come!

Hello friend,

I'm no doctor or educator or nutritional or anything important, but being the problem you have, could you try cutting one or the other out? For example day one have a bagel and milk, Day two have apple and and milk? Again, I'm no doctor but I personally am afraid of blousing that much insulin. As it sits now I take about 160-180 carbs per day and I'm at a 1:4.

Just suggestions?

Hi…wow! Lots of insulin for sure. Have you seen a nutritionist? How about substituting whole wheat toast for that bagel? Or multi-grain (the kind where you can actually see the stuff in it). You could almost have two slices for that one bagel! How about having eggs occasionally instead of one of those other carbs? Have the milk or…I sometimes mix water half and half with juice. Not bad really. Eat the apple a couple hours later as a snack. I’ m not a nutritionist either. That’s just a lot lot of carbs at one time!

Thanks for all your suggestions on this. Spreading out the carbs and making better chooses is the way I'm handling it. I'll get by :-)

The 25 unit limit is not easy to get around so I have to bolus twice any time I eat 38 carbs or more. This makes it easy to forget if I don't hear the reminder. A 25 unit bolus at 1 unit per 20 seconds will take 8 minutes to deliver, that's enough time for me to forget when I don't hear the warning (I have a hard time hearing my pumps in my pocket sometimes).

I will get used to it and be just fine, but it was just something I wasn't aware of and would have liked to know it ahead of time while making my decision on what pump I wanted to go with.

I do love the pump!!!

Thanks again!

My insulin to carb ratio is 1:7. I’ve only had 3 or 4 times when I exceeded the “governor” set by my Endo. I believe that all pumps have a FDA mandated maximum bonus limit. You ARE constrained by that I/C of 1:1.5. Yikes!



My educational classes helped tremendously. It taught me how to read labels–I don’t do very many prepared foods except cereals. Some foods “sound” healthy, but aren’t…bagels for example.



You’ll get there. I recalled being seriously pi$$ed once I realized that I had to account for every single little teeny tiny itty bitty thing that I ate!

I love my pump! Oh yes, the blouse max WAS set at 10 when I was on the OmniPod. I did have the option to override though.

I would love to have a ratio of 1:7, it would make things a little nicer!!! All those type 1's that have a 1:25 ratio or better, I can't image :-)

This is my 5th pump and have been counting carbs for a long time. Some periods of time over the years I'm very good at it and my A1Cs are around 5.8 and other period of times I have A1Cs in the 9 range. I am currently and have been in the past being treated for an eating disorder, when the disorder really kicks in I stop counting carbs and ignoring my diabetes, but it is killing me (literally). I've had dozens of hours in dietary training but knowing and doing are 2 totally different things.

Thanks for the support and I do love my pump too :-)

That eating disorder thing is very very difficult to deal with. Unlike many others, you HAVE to eat to live! My granddaughter has an I:C ration of 1:20. I have a family history of diabetes. I never met my grandfather because insulin came into use the year after his death at the age of 28. My first experience with seeing someone living with diabetes was when a man who was renting an apartment from my parents came over to boil his needles! He hadn’t had his utilities turned on yet! Can you imagine?! I think of him when I find my self frustrated with the whole issue of coping.

I sometimes forget too. I use vibrate instead of audible alarm, which I always feel in my pocket when it confirms delivery is completed

I did not know this either. My bolus using MDI is 1:1. I try to keep my carb intake very low because I've found that the insulin just doesn't work as well if I eat a lot of carbs, but even so, that's frustrating. I would never eat the breakfast you eat, though. Your breakfast would be a full syringe of insulin for me.

I did not know of this limitation. Since I tend to eat very low carb anyway (I try to stay below 30 carbs a day) then it shouldn't effect me often, but occasionally it will.

Good grief.

You won’t have a problem with 30 carbs/day. You would have to bolus twice to eat a meal with more than 25 carbs…limit of 50 carbs/meal for you.

Yeah, that's what I was thinking. I usually eat less than 10 carbs a meal and since I graze more than I eat meals I expect managing stacking will be a bigger issue for me. Occasionally, though, I want some fries! :D

I realize this is an old post, but you can set your max bolus rate in your settings.

I can bolous for more…it will do the initial 25 and after it is done…will ask if you wish to do the rest…and I hit yes. So there is no bolous limit per say.

The Original Poster is accurate. The tslim will only string 2 maximum boluses together. So if you need more than 50u of insulin at once it won't do it. You have to string two together and then remember to take that third bolus yourself.

I switched to u500 insulin in the pump. It's off label use but it works well enough if you are willing to bolus much farther ahead. Docs will tell you a half hour, but to prevent post prandial spikes I end up having to wait 1 hour to 1.5 hours after a bolus to eat. Most u100 bolus insulin peaks in about 2 hours but u500 peaks at about 4 hours. So it's a bit like managing with an insulin that is half way between a bolus and a basal insulin. It takes a lot of planning but it's very doable.

I got my A1c down to 5.7 (from 12.9). It's doable.

Congrats on the A1c of 5.7!!! That was my last A1c too! Now after almost a year and a half on the pump and using a CGM (continuous glucose monitor) I have learned to use the pump but it is not ideal. There are times that I don't hear the "beep" to continue on with the second 25 unit bolus and forget about it until I hear the warning later, or times I forget to program another bolus to cover a larger meal. The CGM has become a major roll in my A1c being at 5.7 because with the T:slim's limits, it causes me to default to be high a lot of the time and the CGM helps me see the changes/trends in my BG levels and I can treat them early.

I thought about going to u500 because I am using about 340 units a day and that means I am changing my cartage on average of more that once a day, but I don't have to plan/bolus so far ahead for every meal either.

Good luck and good work on that A1c!!!