Which of the following belongs to NaSSA group of drugs?
**Core Concept**
The NaSSA group of drugs refers to a class of medications that act on the nervous system by modulating the activity of serotonin and norepinephrine in the brain, thereby exerting anxiolytic, antidepressant, and sedative effects. These drugs primarily target the serotonin receptors and the adrenergic system.
**Why the Correct Answer is Right**
Mirtazapine is a tetracyclic antidepressant that belongs to the NaSSA group of drugs. It works by blocking the presynaptic alpha-2 adrenergic receptors, thereby increasing the release of norepinephrine and serotonin. Additionally, mirtazapine acts as an antagonist at the central serotonin 5-HT2 and 5-HT3 receptors, which contributes to its anxiolytic and sedative effects. The blockade of serotonin receptors also has a disinhibitory effect on the firing of neurons, further contributing to its antidepressant action.
**Why Each Wrong Option is Incorrect**
**Option A:** Mianserin is another tetracyclic antidepressant, but it is not a NaSSA drug. Instead, it is a serotonin receptor antagonist and a norepinephrine reuptake inhibitor.
**Option B:** Reboxetine is a norepinephrine reuptake inhibitor but not a NaSSA drug.
**Option C:** Amitriptyline is a tricyclic antidepressant that primarily works by inhibiting the reuptake of serotonin and norepinephrine, but it is not classified as a NaSSA drug.
**Clinical Pearl / High-Yield Fact**
Mirtazapine is known for its sedative effects, making it a good option for patients who have difficulty sleeping. However, it can also cause weight gain and increased appetite, which should be monitored in patients with a history of obesity.
**Correct Answer: C. Mirtazapine**