The main symptom of hyperglycemia includes which of the following?

The primary symptom of hyperglycemia is increased thirst and frequent urination. When blood glucose levels rise significantly, the kidneys begin to filter out the excess glucose from the bloodstream. This process leads to an increase in urine production, a condition known as osmotic diuresis. As the body loses more fluid through urination, it results in dehydration, which in turn causes excessive thirst, prompting individuals to drink more liquids.

The other symptoms mentioned, such as increased appetite, nausea, vomiting, and muscle cramps, can occur with various conditions but are not the hallmark symptoms of hyperglycemia. Increased appetite is more associated with conditions like uncontrolled diabetes or reactive hypoglycemia rather than a direct result of hyperglycemia. Nausea, vomiting, and muscle cramps can be caused by other factors and are not specific indicators of elevated blood glucose levels. Therefore, the combination of increased thirst and frequent urination is key in identifying hyperglycemia.