To perform the assay of Chlorpheniramine maleate - Practical

 Aim: To perform the assay of Chlorpheniramine maleate.

Molecular Formula: C16H19CIN2, C4H4O4

Mol. Wt.: 390.9

Chlorpheniramine maleate contains not less than 98.0 percent and not more than 101.0 percent of C16H19CIN2, C4H4O4, calculated on dried basis.

Category: Antihistaminic.

Dose: Orally, 4 to 16 mg daily, in divided doses. By subcutaneous or intramuscular injection, 10 to 20 mg, repeated if required; maximum 40 mg in 24 hours. By slow intravenous injection over 1 minute, 10 to 20 mg diluted in the syringe with 5 to 10 ml of blood.

Description: A white, crystalline powder; odourless.

Assay:

• Weigh accurately about 0.2 g and dissolve in 20 ml of anhydrous glacial acetic acid.
• Titrate with 0.1 M perchloric acid, determining the end-point potentiometrically.
• Carry out a blank titration.

Factor: 1 ml of 0.1 M perchloric acid is equivalent to 0.01954 g of C16H19CIN2, C4H4O4.

Storage: Store protected from light and moisture.

Uses: It is used as antihistaminic drug.