What condition does NPH insulin primarily control in individuals with diabetes mellitus?

NPH insulin primarily controls hyperglycemia in individuals with diabetes mellitus. This type of insulin is an intermediate-acting formulation that helps to regulate blood glucose levels over an extended period. By mimicking the natural insulin response of the pancreas, NPH insulin aids in lowering high blood sugar levels that occur after meals and throughout the day, especially when used in conjunction with other insulins or diabetes medications.

When considering the other conditions mentioned, hypoglycemia refers to low blood sugar levels, which NPH insulin can inadvertently cause if too much is administered or if meals are skipped. Ketosis is a condition characterized by elevated ketone bodies in the blood due to a lack of insulin, often seen in type 1 diabetes. While NPH insulin helps prevent ketosis by providing necessary insulin, its primary role is to control excess glucose levels rather than directly managing ketosis. Insulin resistance, which is a reduced response of cells to insulin, relates more to the body's sensitivity to insulin rather than direct control by any specific insulin formulation like NPH.