Indications
Cinnarizine is utilized in the medical management of several conditions related to vestibular disturbances. It is primarily indicated for the treatment of vertigo and Meniere's disease. Additionally, it is effective in addressing nausea and vomiting associated with motion sickness and is beneficial for alleviating vestibular symptoms of other origins.
Pharmacodynamics
As an antihistamine and calcium channel blocker, Cinnarizine exhibits a dual mechanism of action. It acts as a competitive antagonist at histamine H1 receptors, which are involved in various physiological processes, such as the contraction of smooth muscles in the airways and gastrointestinal tract, vasodilation, cardiac stimulation, the secretion of gastric acid, interleukin release, and chemotaxis of eosinophils and mast cells. Cinnarizine belongs to the sedating category of H1 receptor antagonists and also blocks muscarinic acetylcholine receptors, contributing to its effectiveness as an anti-emetic agent. Furthermore, by inhibiting calcium channels, Cinnarizine reduces the stimulation of the vestibular system, thereby mitigating symptoms of dizziness and balance disorders.
Mechanism of Action
Cinnarizine functions by inhibiting the contractions of vascular smooth muscle cells through the blockade of L-type and T-type voltage-gated calcium channels. Additionally, it exhibits binding affinity to dopamine D2 receptors, histamine H1 receptors, and muscarinic acetylcholine receptors. This multifaceted interaction underpins its therapeutic effects.
