Which of the following is an example of an adverse drug reaction?

An example of an adverse drug reaction is represented by fatigue, confusion, and dizziness. Adverse drug reactions can manifest in various ways, including physical, cognitive, and emotional symptoms. The combination of fatigue, confusion, and dizziness indicates a more complex set of reactions affecting the patient's energy levels and cognitive function, often leading to significant impairment in daily activities and quality of life. These symptoms can be challenging to manage and may necessitate medical intervention or adjustment of the medication regimen.

While symptoms like nausea and mild headaches can also occur due to medications, they may not consistently represent more serious adverse effects, whereas the combination of fatigue, confusion, and dizziness signifies a broader and potentially more severe impact on a patient's health. An allergic rash is a specific type of adverse reaction often associated with a particular allergy but does not encompass the range of systemic effects that the correct answer provides, illustrating a more complex and potentially dangerous reaction to a drug.