Is insulin suspension all that it is cracked up to be?

I am vacillating between the Omnipod and Medtronic with insulin suspension (640G I believe.) No tubing with the Omnipod is super attractive, as well as the integrated CGM and insulin suspension capability with the Medtronic.

I run low at night and currently use the Dexcom CGM with multiple injections to manage my T1D which I have had for 40 years. My last A1c was 7.3. My sleep is often compromised due to night time lows, so insulin suspension, in my mind would greatly improve the quality of my sleep. Provided that the integrated CGM with the Medtronics is accurate, I am leaning toward the Medtronic despite the nuisance of tubing. However, I am very concerned with the abundance of online customer feedback regarding the inaccuracy of the integrated CGM and sensor failure rate.

Additionally my diabetes nurse practitioner is advising that insulin suspension is not intended to work seamlessly without me being notified of the lows (alarms which I despise), and in actuality I would still need to wake up and treat the low with carbs.

I really want to hear people’s opinions about if insulin suspension is all that it is cracked up to be? Is it a “concept” Medtronic uses to market and sell pumps with little real life benefit (fluff if you will), or is it legit with true everyday benefits? Have people had their insulin suspended without knowing about it which is how I would like it to work. Much appreciation for helping me whack through the pump weeds to figure out what is real verses marketing.

OmniPod is the only pump I’ve used BUT I want to tell you that you CAN suspend insulin delivery from 1/2 hour to 2 hours in 1/2 hour increments. I absolutely love this feature! Many times while shopping I know I’m falling and will suspend insulin flow. When I get to a restaurant I will Resume Delivery. It’s that simple!

Hi @JenHope,

I currently have medtronic’s most current US model- the 640G with Threshold Suspend and the Enlite Sensor.
Now, this is my perspective only. I have had the 640G model with Enlite sensors since Oct 2013, a little over 2.5 years. I have been on a medtronic pump since April 2013.
I love the 640G model, I love the Enlite Sensor model too. Compared to their other sensor model, it rarely hurts when I insert it (which the previous one did immensely) and I find it to be more accurate than the last model. I find very little problems with it. So I wear mine for the recommended a little over 6 days and within those days there is maybe a 2 at the most moments where it is inaccurate, if that. Most of the time, its pretty spot on. Spot on meaning, I’m within the 10 points of the reading if not dead on with the reading.

The deal with Threshold Suspend- Its great if you know how to use it and you want to use it. So lets say you set your low BG alarm to 60. 60 hits and the alarm will go off (I don’t use predictive alert alarms, too annoying) for threshold suspend, clear it, then the screen will pop up a choice- suspend or resume basal. If you are asleep and you don’t hear the alarm, it will automatically suspend for you. Then, I cannot remember how long maybe a couple minutes or so the threshold suspend alarm goes off again. it wants you to check your blood sugar from correcting or just check your blood sugar.
Now, the only issue I have with it is at night. Most of the time, I sleep through the alarms and it will suspend automatically. Then I wake up with a high BG. Other than that, it works great during the day.
I usually suspend until I can treat, treat then check BG and resume basal.
You can always shut off the threshold suspend, I just checked and you can for sure.
The threshold suspend feature has saved me from using my glucogon a couple of times. It doesn’t automatically shut off though.

Let me know if you have any other questions about it.
Best wishes on your choice.

so i have, the OmniPod, & yes i can, suspend insulin delivery, from 1/2 hour to 2 hours in 1/2 hour, increments.
& i do that, a lot, like when, i’m at school, going from, class, i will suspend insulin delivery, & when i can eat, i Resume Delivery,. i love my OmniPod,.

let me know, if you have any other questions, about the OmniPod,.

I’ve never used a Medtronics pump and certainly not the 640G. Been using the Dexcom CGM for several years and love it. I have used both tubed pump (Animas Vibe) and the Omnipod. Personally, I found the Omnipod’s extra weight connected to my skin to be MORE annoying than the tubing. I’ve used both long and short tubing, though most of the time, the longer tubing has been simpler to tuck in, etc. The choice of infusion set styles is also a benefit that the tubed pumps offer that is not offered by Omnipod. Though I don’t have the Medtronics pumps, I believe that Medtronics allows for fractional I:C ratios (neither Omnipod nor Animas allow that) – this might give you more granular control.

Finally, you’re concerned about the nighttime lows waking you – Nighttime lows are one of the main reasons I switched to a pump. The ability to set multiple basal rates, rather than a stable basal on MDI, has virtually ELIMINATED nighttime lows from my life. Sure, I’ll make a late-dinner bolus error from time-to-time and have a problem , but with the pump, I have had FAR. far fewer lows than I did previously. Something to consider.

Good luck - there is no bad choice here.

No, you don’t unless you are in a clinical trial of the 640G or obtained it though some other means.

In the US, the newest Medtronic pump is the 530G, not 640G. The 640G is only available outside the US at this time.

I think for the 530G, which I am fairly sure is the US pump you nurse was talking about, the basal suspension feature sounds to me like one big PITA. First, it only shuts off after the CGM Sensor Glucose (SG) drops below a set point. I believe it still alarms when/if it does suspend. Also, once it suspends I think it stays suspended until you actually manually resume the basal delivery.

It’s not something I would want to mess with. It sounds to me like a good idea poorly executed.

On the other hand, the newer Minimed 640G now sold in the UK, (some parts of?) Europe, and Australia does a predictive suspend of the basal. If the software in the pump determines that the trend of your basal is dropping and your SG is expected to pass below the threshold limit you set, then the pump suspends the basal delivery.

What’s better about this? First, it (hopefully) stops the basal before you actually go “too low”. Second, the pump will also resume the basal if your SGs rise. Third, you can shut off the alarms so all of this happens in the background without actually waking you up. In other words, with the 640G the suspend/resume can be “seamless”. The pump does it “under the covers” and most people don’t have to manually intervene.

For people who get good results using Medtronic’s CGM, the 640G can be a very powerful tool. However, there are two gotchas. One is that the 640G is not likely to be available in the US until the end of 2016.

The other is that you need to be on good terms with Medtronic’s CGM. At the very least before going this route I would advise you to do a trial run with their CGM just to see how it works for you. If you do that, you might also want to wait until after the 640G is available because Medtronic uses a newer transmitter for that CGM. If you test with the CGM currently available in the US it would be similar, but not what is used with the 640G.

Are you able to tell what causes your nightly lows from your Dexcom CGM? Is it because you need to be able to reduce your basal rate during the night? If that’s the case you might be happiest just going with a pump which is adequate enough for you and then using your Dex to fine tune your basals.


this is a bit off-topic. however, as you are on MDI, have you considered / can you ask your NP about trialing the new insulin Tresiba. I have found it is very steady over night, with much less variation than other insulins I have used in the past (Humalin-R, Levermir).

Of course, a pump is still an option…

Hello, I want you to know I currently use the Medtorinc 640G and a Dexcom G5 sensor. I have been a Medtronic user for 15 years and a excom user for two years. I have never used the omnipod.but well maybe someday, who knows.

My opinion is that I believe the Medtronicc bump is terrific and i like the dexcom system. I hipe I cna someday get my decides back together but unto then it will be sidifficit.

my advice do what your doctor suffered tht is the best advice i can give


Oh my goodness, @irrational_John is right! Yikes, so sorry. I got the models mixed up.
I truly apologize for this. I have the 530G with Enlite Sensor. Thanks for the catch there! :wink:

Everything I mentioned regarding the threshold suspend feature is still correct. I mentioned that you, the pump user has to clear the threshold suspend alarm or Shut it off. Its not perfect, I never said that, but it works and has helped and stopped me from using my glucogon kits a couple of times. I would rather have it than not.

Until we can actually use the 640G in the US, looks like 530G with Enlite sensor is the only option from Medtronic. Just sharing my experience. I find to be a good one. Again, I have been using this system for 2.5 years. I am a mother of 3, soon to be 4. I rely heavily on my pump and CGM system. its pretty important for me.

I completely agree with @irrational_John, you should do a trial run with Medtronic’s pump and CGM. I’m not familiar with this process but I would start by talking to your endo and finding a local medtronic rep, if you are interested in next steps.

As for the tubing, you can get long or short tubing for the infusion sets. With the long tubing, i get stuck on door handles, children, etc. With the short tubing, it pretty much hides in my clothes very well.

You need to find what is going to work for you with your life.

Best wishes with your decision,


I am based in the UK and use the 640g with the “Enhanced” Enlites.

The insulin suspension a.k.a smart guard is actually impressive, once configured correctly and with alarms silenced during the night I often awake to see that my pump has kicked in for an hour or two during the night, suspended insulin and saved me from a low.

It’s the best feature of the pump in my opinion.

I need to do a basal tweak as the pump suspends on average for around two hours every day at various points at the moment, but I try to keep my sugars constantly between 4.8-8.0 pre and post meal through sugar surfing, so it’s easy to trip up!

I’ve got to the point with sensor positioning etc that I trust the pump and silence the alarms, it’s exhausting to have all the alarms and vibrations on 24/7 and is sure fire way to diabetes burnout and stacking insulin to avoid highs, trust me.

The sensors are decent, not as good as the latest dexcom but not far behind, I can get around 14-20 days if I restart the sensor, but I am now funded so replace them once a week. I don’t particularly enjoy having a sensor in me for 20 odd days, they start to go a bit manky, smelly and I’m more prone to site issues after the second week. Pleased I no longer have to stretch sensors really.

I consistently have decent ISIGS, MARDs and I find the sensor accurate if it is positioned and inserted properly.

Negatives of the pump, it’s bulky and the largest pump I’ve had, doesn’t hide easily under clothes against the skin, so I’ve taken wearing it on my hip.

The clip on the 640g is absolute rubbish, I’ve had four replacements in under a year, they are made of weak plastic and I’ve snapped them on seat belts, door handles etc, also had one pump replaced as I broke the clip housing in a similar fashion.

Medtronic admitted to me that the clip was too strong on the previous iterations 530G and the earlier models and that it often caused the pump to break before the clip during accidents/issues.

The new clip is an attempt to rectify this, but they’ve gone too far the other way and it’s too weak in my opinion, I now have a couple of spare clips for when I invariably break this new one in a few weeks.

Also, they are quite battery hungry devices 3-4 weeks with a Lithium if you are lucky, less with an alkaline, 12 days tops in my experience.

Tubing, it’s more reliable than the pod alternative and tubed pumps can be worn in belts under clothing so you never see it. I’ve tried a pod (omnipod) and found it more intrusive and more irritating than the tubed variants.

All in all, I still think the 640g is a better pump than the animas vibe, roche insight and omnipod which I also had a look at when I was making my choice.

It’s not perfect and there a few niggles, but it’s a solid piece of kit.

I’d be tempted by G5 dexcom smart phone/watch set up and a standalone small pump if I was self-funding sensors I think.

I have to ask. If you have such detailed attention to your control, why do you think insulin suspend will make any difference? Personally I think insulin suspend makes sense for someone who isn’t going to look at their CGM when the alarms go off (particularly at night) and perhaps won’t act on the alarm. If you already pay attention to your CGM 24/7 and act on it appropriately then the suspend feature is not likely to benefit you all.

Hi Brian,

If I’m honest, I don’t follow the CGM 24/7 as when I did that I just found it exhausting.

What I like about the suspend feature is instead of say waking up at a potential low alarm at 2am and having to consume 15-20g of carbs, deal with the alarm, struggle to get back to sleep. The pump will suspend and save me the hassle. This is only really useful when you’ve got just basal on board over night and doesn’t work as well if you’ve miscalculated a pre meal bolus.

I think I definitely get less disturbed sleep and am consuming less glucose/calories and insulin due to the suspend which I think is a positive. The fact that I can also silence the alarms, ignore the CGM more and have a bit more trust in the system is also a step in the right direction.

I do however know that if I properly tightened up on everything I’d not have to rely on the suspend, but I just find that a tricky balance at the moment, especially when exercise, stress, illness etc is added to the mix.

On the negative side, it can occasionally suspend for too long and I’ve woken up a couple of points higher than if I’d woken up and treated it directly!

So not perfect, but a useful tool.

Ok, I guess that makes sense. The whole 24/7/365 CGM thing has also been a factor in my not getting a CGM. My doctor has referred me to Dexcom but I haven’t done anything. In my case the real question is whether having all that data and alarms going off will really lead me to any significant improvement in either my diabetes or my quality of life. I’m not so sure.

And I know that I struggle with sleep issues. In my case, being woken up multiple times in the night is far worse than waking a few points high. I can deal with a high in the morning with a correction, I can’t so easily get back that disturbed sleep.

I like insulin suspend. I don’t turn mine off but catch 60s with a 7% basal rate (lucky number…) pretty easily. I also think that with the alarms, etc., it will be useful and offer an additional safety cushion that people can find useful.

Yes, I had the dexcom for a few weeks and it just burnt me out, when I CGM full time I’ve only managed a 0.5% reduction in HbA1c overall, which given lab tolerances is pretty meaningless. I do have less night time lows and use less insulin in general when I go full time with CGM though. It smooths things out a little.

If I wake up with a low at 2/3am chances are I won’t be going back to sleep as I really struggle with sleep generally, I’ll be stressing about checking my sugar again, waking up high, annoyed about losing sleep etc.

I think they have their uses, good tools for anxious parents with young type 1s no doubt, useful for training in sports and good for those with nocturnal hypoglycemia, defo not for everyone, especially if you’re settled in a routine and have decent control already.