If calcium levels are low and PTH levels are normal or low, then PTH is not responding properly and the person tested probably has hypoparathyroidism. Hypoparathyroidism is a failure of the parathyroid glands to produce sufficient PTH.
Heat exhaustion definition and facts. 1  Heat exhaustion is one part of the spectrum of heat-related illnesses that begin with heat cramps, progresses to heat exhaustion, and finally to heat stroke.  The body cools itself by sweating and allowing that sweat to evaporate.
1 Causes of heat exhaustion is activity in a hot environment can overwhelm the body's ability to cool itself, causing heat-related symptoms. 2  Symptoms of heat exhaustion include. 3  profuse sweating, 4  weakness, 5  nausea, 6  vomiting, 7  headache, 8  lightheadedness, and. 9  muscle cramps.