If there is marked pallor (whiteness), ischemia should be suspected.
en.wikipedia.org Some of these symptoms include pallor, sweating, nausea, vomit, changes in vital signs including blood pressure, heart rate and/or temperature.
en.wikipedia.org It is not usually clinically significant unless it is accompanied by a general pallor (pale lips, tongue, palms, mouth and other regions with mucous membranes).
en.wikipedia.org After the insulin injection patients would experience various symptoms of decreased blood glucose: flushing, pallor, perspiration, salivation, drowsiness or restlessness.
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