Which sequence correctly orders impairment of consciousness from mild to deepest level?

Which sequence correctly orders impairment of consciousness from mild to deepest level?

• A. Lethargy, obtundation, stupor, coma
• B. Coma, stupor, obtundation, lethargy
• C. Obtundation, lethargy, coma, stupor
• D. Stupor, coma, lethargy, obtundation

Answer: (A)

Progression of consciousness impairment goes from mild to deepest: lethargy, obtundation, stupor, then coma. Lethargy means the person is drowsy but arousable and can respond, though slowly. Obtundation is a deeper reduction in alertness requiring stronger stimulation to wake, with slower and less coherent responses. Stupor is much more depressed—little spontaneous movement, and only vigorous or painful stimuli provoke a brief, often nonpurposeful reaction. Coma is the deepest state, with no meaningful arousal or purposeful response to any stimulus. Because coma is the deepest level, the correct ordering places it last, after lethargy, obtundation, and stupor.