Hi,

I was doing some research to find out if the new Magnesium dosage that is making me lightheaded or it's the new Diltiazem SR dosage.
I found this online:

Blood Pressure Medications, Calcium Channel Blockers
Magnesium may increase the likelihood of negative side effects (such as dizziness, nausea, and fluid retention) from calcium channel blockers (particularly nifedipine) in pregnant women. Other calcium channel blockers include amlodipine, diltiazem, felodipine, and verapamil.

The article said "in pregnant women" but maybe it can happen to anyone. Anyway, in the next few days I will go back to my old dosage of both Magnesium and Diltiazem and see what I feel.

Thanks,
Michael