Narcolepsy with cataplexy is typically characterized by which features?

• A. Excessive daytime sleepiness with sudden loss of muscle tone triggered by emotion.
• B. Insomnia with sleepwalking.
• C. Restless legs symptoms at night.
• D. Obstructive sleep apnea with snoring.

Answer: (A)

The key idea is that narcolepsy with cataplexy combines persistent daytime sleepiness with sudden, emotion-triggered loss of muscle tone. Cataplexy is a brief, reversible drop in voluntary muscle strength while consciousness remains, often sparked by strong emotions like laughter or surprise. This specific pairing—excessive daytime sleepiness plus cataplexy—definingly characterizes narcolepsy with cataplexy. Other options describe different sleep problems—insomnia with sleepwalking (a parasomnia), restless legs at night, and obstructive sleep apnea with snoring—without the hallmark cataplexy component.