Which of the following is a sympathetic effect of hypoglycaemia?

The sympathetic effects of hypoglycaemia primarily relate to the body’s stress response. When blood glucose levels drop, the body reacts through the sympathetic nervous system, leading to a number of physiological responses aimed at restoring glucose levels.

Fatigue is commonly associated with hypoglycaemia, but in this context, it's important to recognize its link to sympathoadrenal activation. The body releases adrenaline (epinephrine) to mobilize energy stores, but this process can often leave a person feeling drained after the immediate symptoms subside. In the state of hypoglycaemia, the hormones released can cause a feeling of weakness or decreased energy levels, manifesting as fatigue.

In contrast, confusion, slurred speech, and nightmares can be attributed to neurological symptoms or psychological effects rather than directly being caused by sympathetic activation. Confusion and slurred speech more directly reflect the brain's response to inadequate glucose supply, while nightmares may be related to stress or anxiety rather than an immediate sympathetic effect. Therefore, fatigue reflects a sympathetic response to low blood sugar, making it the most relevant choice in this context.