Final answer:
Gradually decreasing the administration of IV glucose is necessary to prevent a hypoglycemic reaction because it ensures a controlled reduction in blood glucose levels, rather than a sudden drop.
Step-by-step explanation:
Hypoglycemia is a condition that occurs when the blood glucose level falls below the normal range. The brain uses glucose as its main source of energy, so insufficient supply of glucose to the brain can lead to symptoms such as convulsions, sweating, weakness, and coma. Gradually decreasing the administration of IV glucose is necessary to prevent a hypoglycemic reaction because it ensures a controlled reduction in blood glucose levels, rather than a sudden drop.