Cinnarizine used for motion sickness is a
**Core Concept**
Cinnarizine is a medication used to treat motion sickness, vertigo, and other vestibular disorders. It belongs to a class of drugs known as calcium channel blockers and antihistamines, which have a synergistic effect in alleviating symptoms of motion sickness.
**Why the Correct Answer is Right**
Cinnarizine acts by blocking calcium channels in the inner ear, thereby reducing the vestibular-ocular reflex (VOR) that is responsible for motion sickness. It also has antihistaminic properties, which help to reduce the excitability of the vestibular system and alleviate symptoms such as nausea and vomiting. The combination of its calcium channel blocking and antihistaminic effects makes cinnarizine an effective treatment for motion sickness.
**Why Each Wrong Option is Incorrect**
**Option A:** Cinnarizine is not a dopamine antagonist, which is a different class of medication used to treat motion sickness (e.g., metoclopramide).
**Option B:** Cinnarizine is not a selective serotonin reuptake inhibitor (SSRI), which is a class of antidepressants that can sometimes be used to treat nausea and vomiting.
**Option C:** Cinnarizine is not a benzodiazepine, which is a class of sedatives that can sometimes be used to treat anxiety-related symptoms of motion sickness.
**Clinical Pearl / High-Yield Fact**
It's worth noting that cinnarizine can cause drowsiness as a side effect, so it's often used in combination with other medications to treat motion sickness.
**Correct Answer:** C. Cinnarizine is a calcium channel blocker and antihistamine.