Which condition is least likely to cause an altered level of consciousness?

• A. Acute anxiety
• B. Poisoning
• C. Inadequate perfusion
• D. Drug overdose

Answer: (A)

Altered level of consciousness happens when the brain isn’t functioning normally due to impaired blood flow, lack of oxygen, metabolic problems, or toxins affecting the CNS. Poisoning and drug overdose can depress brain activity directly, and inadequate perfusion reduces oxygen and nutrients to the brain, leading to confusion, drowsiness, or coma. Acute anxiety, by contrast, is a psychological state that may cause distress and autonomic symptoms, but it does not typically disrupt the brain’s level of consciousness. People remain awake and oriented unless there’s another medical issue. So acute anxiety is least likely to cause an altered level of consciousness.