A 4-yrs-old boy is brought to the physician by his parents for episodes of waking in the middle of the night screaming. The parents state that when they get to the boy’s room during one of these episodes, they find him in his bed, thrashing wildly, his eyes wide open. He pushes them away when they try to comfort him. After 2 min, the boy suddenly falls asleep, and the next day he has no memory of the episode. Which of the following medication is used to treat this disorder?

**Core Concept**
Sleep terrors, also known as night terrors, are a type of parasomnia that occurs during deep non-rapid eye movement (NREM) sleep. They are characterized by intense fear, confusion, and disorientation, often accompanied by thrashing, screaming, and a lack of response to environmental stimuli.

**Why the Correct Answer is Right**
The medication used to treat sleep terrors is typically a benzodiazepine or a non-benzodiazepine hypnotic, which can help regulate sleep patterns and reduce the frequency of episodes. Clonazepam, a benzodiazepine, is often prescribed for its sedative and anxiolytic properties, which can help alleviate symptoms of sleep terrors. Clonazepam works by enhancing the activity of the neurotransmitter gamma-aminobutyric acid (GABA), which has a calming effect on the nervous system.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because medications like melatonin are typically used to treat insomnia or sleep disorders that involve difficulty falling asleep, rather than sleep terrors.
**Option B:** This option is incorrect because selective serotonin reuptake inhibitors (SSRIs) are primarily used to treat depression, anxiety disorders, and other mood disorders, rather than sleep terrors.
**Option C:** This option is incorrect because antihistamines are often used to treat allergies and other conditions, and are not typically used to treat sleep terrors.

**Clinical Pearl / High-Yield Fact**
It's essential to differentiate between sleep terrors and nightmares, as the treatment approaches differ. Nightmares occur during the rapid eye movement (REM) stage of sleep, typically in the latter part of the night, and are often associated with vivid, disturbing dreams.

**Correct Answer:** C. Clonazepam

✓ Correct Answer: B. Diazepam