Brief Answer:
no interaction causing increase in blood sugar

Detailed Answer:
HI, thanks for using healthcare magic

There is a risk of interaction between two of the medications- the cardizem and the metformin but it is minor and may not occur in everyone. It is quite likely that it is not occurring for you.

Cardizem can increase the effect or level of metformin slightly, if this occurs it would cause a decrease in blood sugars not increase. As stated, it does not occur with everyone and since you are having an increase in readings, it is not happening in your case.

There is no other potential combination here that can cause increase blood sugar.

If you are acutely ill in any way, it may be part of the body's stress response but if this is not the case, the increase may be due to slight changes in diet or activity or reflect progression of the diabetes.

Diabetes can progress

I hope this helps, feel free to ask any other questions

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