Which Ingredients Of Levocarb Cause Side Effects?

I am on 2 25/100 levocarb/day (breakfast & supper) with no side effects for 6 months. If I take a 3rd pill at noon I experience difficulty breathing, as if I'd run up and down stairs. I know it's the pill because I have experimented several times with it. I'm wondering what the fillers are as perhaps they are the culprit.

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