Medtronic GS3 Sensors - Reliability

Has anyone noticed the reliability and accuracy of Medtronic GS3 sensors changing for the worse lately? The last 4 sensors I have used have been remarkably inaccurate. For example, the sensor will give a reading of 2.8 and the pump then beeps and warns me it is suspending on low. But when I do a blood test on my meter, I am at 5.7. Or my pump will beep and warn me to check ketones because the reading from the sensor is over 18.0 And when I check my blood on my meter, I am at 7.7 There is no pattern to the variation but it is incredibly frustrating. I do not dare to use the SmartGuard feature because it would be making entirely unwarranted adjustments. I have ended up replacing the last two sensors after only 3 days because the readings were completely useless to me. And I am quite certain it is not something I am doing wrong, because I have been using these sensors for years and have not changed anything in how I apply them or calibrate them. Has anyone had similar experiences? Any ideas on what might be wrong? Thanks.

@Ken1 ,
Is this post current? As in this past April….2024? If so, I didn’t notice any problem with them in my former 670g. They worked fine. Several months ago I switched to 780g and G4 sensors. I had a rough start. Thankfully, it got acclimated and I’m loving it. Very accurate almost all the time. In fact, I read somewhere, that you could use G3 sensors with a G4 transmitter on a 780 pump. It was true. I used one and it worked well for a week.

Ref. The G3 sensors. I did notice that I couldn’t get much time extending them anymore. Years prior, I could extend to 2 weeks or more, but now…I don’t bother extending anymore. I only get 2 extra days, so it’s not worth it.

Maybe there is a transmitter issue. Idk. I know that must be incredibly frustrating. I’d be on the phone with Medtronic.

Yes, it is current. I am in Canada and only the G3 sensors are available on my program so I cannot comment on the G4 sensors. This experience was with the G3s and a 780 pump. Like you, I used to be able to extend the life of the G3 sensors but I haven’t done that for quite a long time so it has nothing to do with that. The last 3 I used have been fairly good again, so maybe I had just had a box of faulty sensors. And yes, I was in touch with Medtronic several times and just got the standard answers, which didn’t help at all.

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I hope your trouble has resolved. Sometimes, things go weird with no real explanation.

I’m getting improved service with my 780 and G4 cgm, but there’s always something.

I had to get up last night at 1:30 a.m. and change my infusion set due to high BG that wouldn’t come down….then when that didn’t help, got back up to change reservoir and new vial of insulin. Man, that finally resolved it, but I’m not sure which was the problem. Insulin? Hmmm…may be throwing away a good vial, but can’t risk it. Not another night like that. The cgm was working well though. Lol