What is your "Low Alarm" setting?

Just curious about what others are using for their low settings.

When I first got the Dexcom, I was on MDI and not under great control. I left the setting at the 70 level (default), and set it off quite regularly. I also tended to hit 70 with the arrow trending down and by the time the alarm went off, I was already in trouble.

I subsequently raised the alarm to 80, and this gave me a little advance warning when I was headed for a dangerous low. When I hit the 80 mark and was trending down, I had a little more time fend it off.

The only problem with that change was the times I would hit 78 or 79 with a flat arrow. Thinking I was okay, I would acknowledge the alarm and feel great about flat lining at such a low level. Problems arose when my flat line was only temporary and then started decreasing again. The next alarm wouldn't go off until I broke the 55 barrier and then I would be in real trouble. This happened a few times and I ended up becoming hyper vigilant whenever I broke that 80 barrier even if the arrow was flat.

Fast forward a few months and now I'm on the OmniPod and feel like I'm really starting to flatten out my daily BG levels. I'm doing a much better job of carb counting and the ability to have my basal levels change throughout the day are doing wonders.

Now I'm back to thinking I should be okay with moving the setting back to 70 and eliminate a lot of my low alarms.

How does every one else handle this?


Mine is set at 70 now. I used to have the same problem and would have it at 80, but 70 works much better for me.

I would say try 70 again and see what happens. Because I am hypoglycemic unaware, my CDE recommended I use 90 for my alarm. Her reasoning was that if I were trending down, taking into account the 20 minute delay of CGM, when the alarm went off I would already be around 70. (I usually don't notice symptoms until I am in the 50s or lower).

I use 80 because I find that the Dexcom tends to show me higher than the Omnipod Freestyle does. I use 80 for my low and 160 or 180 for my high.

I have the opposite problem. My dex shows me lower than my PDM, usually about 10mg/dl on average.

To be honest, it depends for me. When I do my power walks, I like to it set at 90. The reason being is that, because I use insulin, cardio exercises can make your blood sugars lower very rapidly, so I like to have that extra cushion. However, it's been so damn hot here in NYC for the past couple of months, that I have not been wearing my Dex. :-(


I've used the Dexcom for over three years. At the beginning I tried various low alarm settings and finally decided 70 worked the best. It's not too low to intervene if your BG starts to crash but is also helps avoid most of the nuisance low alarms.

I have mine set to 80, but it's also important what time you have set for the 'snooze'. You mentioned times you alarmed at 78-79, and then didn't get another alarm until it hit 55. So either you were dropping fast, or you had a long snooze.

I have my snooze at 30 min for Low. This means that after the alarm at 78-79, and I acknowledge it, if 30 min later I am still under 80, it will alarm again, so I usually avoid the 55 alarm. If the snooze time is higher, it might explain why your next alarm was at 55. Times like that I wish we could set an alarm for the slanted down arrow !

I tried using 70 for my low alert, but found 80 works better for me.

80 is good. Just bump it with a lifesaver candy or other small CHO to bring the the 78 to an 81. You know your body better than anyone else. Working the "trim planes" on your body is like the ones on an airplane or ship. A little goes a long way.

I must be different than the rest of the group with respect to my blood sugar swings. I leave the low alarm set at 100 since there is a 15 minute lag between the Dexcom measurement and your actual BS. If I'm dropping quickly, my actual BS could be 60 or lower when I alarm at 100. I don't mind the alarm and then I look at the trend (and often do a BS finger stick test).

Also since the Dexcom may well be off by 20 points, I don't trust the Dexcom 7 to be that accurate (hopefully its better with the Gen4).

At night I drop the low limit down to 80 to avoid being awaken without a good reason.