Chlorpheniramine Maleate Anti - Allergic Raw Material

Chlorpheniramine maleate Usage And Synthesis

Chemical Properties White Solid

Uses An antagonist of the histamine H1-receptor

Uses Antihistaminic

 

General Description Chlorpheniraminemaleate, (±)2-[p-chloro-α-[2-dimethylamino)ethyl]benzyl]pyridine bimaleate (Chlor-Trimeton), is a white crystallinepowder that is soluble in water (1:3.4), in alcohol(1:10), and in chloroform (1:10). It has a pKa of 9.2, and anaqueous solution has a pH between 4 and 5. Chlorination ofpheniramine in the para position of the phenyl ring increasespotency 10-fold with no appreciable change in toxicity.Most of the antihistaminic activity resides with thedextro isomer (see under “Dexchlorpheniramine Maleate”

 

General Description Odorless white crystalline solid or white powder with a bitter taste. pH (2% aqueous solution) 5. pH (1% aqueous solution) 4-5.

Air & Water Reactions Water soluble.

Reactivity Profile A halogenated amine, ester. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides. Esters react with acids to liberate heat along with alcohols and acids. Strong oxidizing acids may cause a vigorous reaction that is sufficiently exothermic to ignite the reaction products. Heat is also generated by the interaction of esters with caustic solutions.

 

 

Veterinary Drugs and Treatments Antihistamines are used in veterinary medicine to reduce or help prevent histamine mediated adverse effects. Chlorpheniramine is one the more commonly used antihistamines in the cat for the treatment of pruritus. It may also be of benefit as a mild sedative in small animals due to its CNS depressant effects.

 

 

 

Mechanism of action editing

The propanines include bromobenadine, dimedinindine, feniramine, and triplidine, which have strong H1 receptor antagonists and sedative effects. Ethanolamines, including trimethoprim, carbamazine and doxiramine, have significant sedative and anticholinergic effects, with lower gastrointestinal side effects. Ethylenediamines, including mepriramine, chloropyrine, antazoline, cisloxidine, have moderate sedative activity, can cause intestinal disorders and photosensitive reactions. Phenthiazines include parazeazine, promethazine, propionymazine and mequinazine, which have significant anticholinergic and antiemetic effects and can cause sedation and photoanaphylaxis. Piperazines, including cetirizine, buclizine, meclozine, have antiemetic effect. Others are asimidazole, azatadine, tefinazine, avastine, bamipine and loratadine, which are highly selective H1 receptor antagonists. Oral absorption was rapid and complete, effective for 15-60min, the blood concentration reached a peak of 2.5-6h, the first-pass effect was significant, the bioavailability was 25%-50%, t1/2 was 30.3h, the protein binding rate was about 70%, mainly through liver metabolism, metabolites had no pharmacological activity, and part of the original form was discharged from urine.