Antacids<span> that contain magnesium have a laxative </span>effect<span> that may cause diarrhea, and in patients with renal failure they may cause increased magnesium levels in the blood, because of the reduced ability of the kidneys to eliminate magnesium from the body in the urine.</span>
I don't know whether this was one of your options, but South Asia can be very well characterized as a Sub-continent.
In fact, it's is commonly referred to as "the Indian Subcontinent" or even simply "Subcontinent". One of the reason for a distinction of this part of the land is that it lies on a different tectonic plate.
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