Introduction Astemizole, once a notable antihistamine in the treatment of allergies, has a history marked by its withdrawal from the market due to safety concerns. Prescribers traditionally recommended it for allergic rhinitis and chronic idiopathic urticaria, as it is an antagonist at H1 histamine receptors. However, its withdrawal stemmed from the recognition of potentially life-threatening … Read more
Antazoline (Antistine) Introduction Antazoline maleate, a compound blending antazoline—an antihistamine—with maleic acid, stands as a pharmaceutical agent notable for its therapeutic versatility. Functioning as a competitive antagonist at H1 histamine receptors, it effectively alleviates symptoms associated with histamine release. Additionally, its potential antimuscarinic effects contribute to its utility in conditions where a reduction in acetylcholine activity … Read more
Introduction Azatadine is a pharmacological agent celebrated for its role as an antihistamine, contributing to the management of allergic conditions. As a selective antagonist at H1 histamine receptors, azatadine efficiently mitigates the effects of histamine, offering relief from common allergic symptoms such as itching, sneezing, and a runny nose. Widely employed in the treatment of … Read more
Dibenzocycloheptene derivatives” refer to a group of chemical compounds that share a common structural motif of a dibenzocycloheptene ring system. This structure consists of two benzene rings fused to a cycloheptene ring. These derivatives can have various substituents and modifications, leading to a diverse range of compounds with different properties and potential applications. One well-known … Read more
Chlorpheniramine HCl is a widely used antihistamine renowned for its effectiveness in providing relief from symptoms associated with allergic reactions. Functioning as an antagonist at the H1 histamine receptors, it effectively mitigates manifestations such as itching, sneezing, and a runny nose. Commonly employed in treating allergic rhinitis, allergic conjunctivitis, and symptoms related to the common … Read more
Introduction Chlorcyclizine is a piperazine-class antihistamine with antiemetic properties commonly utilized to prevent and relieve nausea and vomiting, particularly in the context of motion sickness. With its mechanism of action as an H1 receptor antagonist, it not only mitigates the effects of histamine but also exhibits antimuscarinic properties, contributing to its effectiveness in managing motion-induced … Read more
Piperazine derivatives” refers to a group of chemical compounds that share the basic structural framework of piperazine. Piperazine is a heterocyclic organic compound containing two nitrogen atoms in a six-membered ring. Derivatives of piperazine can be synthesized by modifying this basic structure through various chemical reactions. Cyclizine (Marezine) Cyclizine is an antihistamine medication that belongs to … Read more
INTRODUCTION Histamine, [2-(imidazol-4-y1) ethylamine], which is biosynthesized by decarboxylation of the essential amino acid histidine, is found in all organs and tissues of the human body. Reaction: Histamine is stored within the secretory granules of mast cells, maintaining a pH of 5.5. It exists in a positively charged state and forms ionic complexes with the … Read more
