%0 Journal Article
%T Spectrophotometric Determination of Some Non-Sedating Antihistamines Using Erythrosine B
%A Michael E. El-Kommos
%A Samia M. El-Gizawy
%A Noha N. Atia
%A Noha M. Hosny
%J ISRN Analytical Chemistry
%D 2013
%R 10.1155/2013/209518
%X A simple and sensitive spectrophotometric method has been developed for the determination of cetirizine (I), ebastine (II), fexofenadine (III), ketotifen (IV), and loratadine (V) based on ion-pair complex formation with erythrosine B. The pink color of the produced complex was measured at 550£¿nm without solvent extraction. Appropriate conditions were established by studying the color reaction between erythrosine B and the studied drugs to obtain the maximum sensitivity. Beer-Lambert's law is obeyed in the concentration ranges 1¨C7, 1¨C8, and 1¨C6£¿ g/mL for (I, IV), (II, III), and (V), respectively. The method was validated according to ICH guidelines. The suggested method is applicable for the determination of the five investigated drugs in bulk and pharmaceutical dosage forms with excellent recoveries. 1. Introduction In 1937, the first H1 antihistamine (thymo-ethyl-diethylamine) was synthesized. However, because of its weak activity and high toxicity, this compound was not used. Clinically useful H1 antihistamines such as phenbenzamine, pyrilamine, and diphenhydramine were introduced in the 1940s. Currently, H1 antihistamines constitute the second most commonly used class of medications after antibiotics. The older first-generation antihistamines are associated with troublesome sedative and antimuscarinic effects and are often termed ¡°sedating antihistamines.¡± The newer generations of antihistamines, which are essentially devoid of these effects, are correspondingly termed ¡°non-sedating antihistamines.¡± Non-sedating antihistamines are of potential value in the management of allergic rhinitis in which they relieve nasal and conjunctival itching, sneezing, and rhinorrhoea. They are also useful in the treatment of acute and chronic urticaria [1]. Non-sedating antihistamines down regulate allergic inflammation directly through the H1-receptor by interfering with histamine action at H1-receptors on sensory neurons and small blood vessels. They also decrease the antigen presentation, expression of pro-inflammatory cytokines and cell adhesion molecules, and chemotaxis. In a concentration-dependent manner, they inhibit mast cell activation and histamine release [2]. Second-generation non-sedating antihistamines investigated are cetirizine (CTZ), ebastine (EBS), ketotifen (KET), and loratadine (LOR), while Fexofenadine (FXD) is one of the third-generation drugs. Their chemical structures are given in Figure 1. Figure 1: Chemical structures of the investigated drugs. The studied drugs, CTZ, EBS, FXD, KET, and LOR are available in cheap generic forms, and they are
%U http://www.hindawi.com/journals/isrn.analytical.chemistry/2013/209518/