How quicly can blood sugar fall?

[Beancounter298]

I had a sandwich for lunch today, which I wouldn't normally do' Out of interest I tested 2 hours later and got a result of 9.8. I was quite alarmed by this so tested again after a further 2 hours and it was down to 4.7. Does this sound reasonable? It seems a big drop quite quickly

 

[Inka]

If it took two hours to go from 9.8 to 4.7, I don’t think that’s quick. That’s about what I’d expect or a bit slower.

Are you on any diabetes meds?

 

[Beancounter298]

I meant that the fall to 4. 7 was quick, which made me wonder how accurate the 9. 8 was

I'm on Metformin, 2000g/day

 

[Lucyr]

I meant that the fall to 4. 7 was quick, which made me wonder how accurate the 9. 8 was

I'm on Metformin, 2000g/day

You said the 4.7 was two hours after the 9.8 though? 2 hours is not quick for that drop.

 

[Inka]

I meant that the fall to 4. 7 was quick, which made me wonder how accurate the 9. 8 was

I'm on Metformin, 2000g/day

I know what you meant and that was what I was replying to. 9.8 to 4.7 two hours later isn’t quick and isn’t anything to worry about 🙂

As I said above:

If it took two hours to go from 9.8 to 4.7, I don’t think that’s quick. That’s about what I’d expect or a bit slower.

 

[Lucyr]

The closest thing I have available to give a numerical definition of fast or slow drop is the libre cgm arrows.

Libre defines a fast drop as more than 0.1mmol per minute so more than 12mmol in 2 hours.

It defines changing slowly as less than 0.06mmol change per minute so less than 7mmol in 2 hours.

 

[Beancounter298]

You said the 4.7 was two hours after the 9.8 though? 2 hours is not quick for that drop.

Thanks, that's what I wasn't sure about, whether it was quick or more typical

 

[PerSpinasAdAstra]

Seems normal enough to me. When testing a couple of months ago some meals would produce a rapid rise and rapid fall, while others were more drawn out. These two screenshots from a Libre 2 are from meals that were quite high in carbs. No two people will have the same responses though - these are just to illustrate that the fall after a meal can vary quite a lot:

 

[Satan’s little helper]

I had a sandwich for lunch today, which I wouldn't normally do' Out of interest I tested 2 hours later and got a result of 9.8. I was quite alarmed by this so tested again after a further 2 hours and it was down to 4.7. Does this sound reasonable? It seems a big drop quite quickly

Where did you come from before lunch? Was there a reading before eating?