(Ph. Eur. 11.6 update)
Action and use
Dopamine receptor antagonist; neuroleptic.
DEFINITION
Chlorpromazine Injection is a sterile solution of Chlorpromazine Hydrochloride in Water for Injections free from dissolved air.
The injection complies with the requirements stated under Parenteral Preparations and with the following requirements.
Content of chlorpromazine hydrochloride, C17H19ClN2S,HCl
95.0 to 105.0% of the stated amount.
CHARACTERISTICS
A colourless or almost colourless solution.
IDENTIFICATION
A. To a volume containing 0.1 g of Chlorpromazine Hydrochloride add 20 mL of water and 2 mL of 10M sodium hydroxide. Shake and extract with 25 mL of ether. Wash the ether layer with two 5 mL quantities of water, dry with anhydrous sodium sulfate, evaporate the ether and dissolve the residue in 1 mL of chloroform. The infrared absorption spectrum of the resulting solution, Appendix II A, is concordant with the reference spectrum of chlorpromazine (RS 056).
B. Complies with the test for identification of phenothiazines, Appendix III A. For solution (1) dilute the injection with water to give a solution containing 0.2% w/v of Chlorpromazine Hydrochloride.
TESTS
Acidity
pH, 5.0 to 6.5, Appendix V L.
Related substances
Carry out the test for related substances in phenothiazines, Appendix III A, using mobile phase A and applying separately to the plate 20 μL of each of the following freshly prepared solutions. For solution (1) dilute a volume of the injection, if necessary, with sufficient of a mixture of 95 volumes of methanol and 5 volumes of diethylamine to produce a solution containing 0.5% w/v of Chlorpromazine Hydrochloride. For solution (2) dilute 1 volume of solution (1) to 20 volumes with the same solvent. For solution (3) dilute 1 volume of solution (1) to 200 volumes with the same solvent. Any secondary spot in the chromatogram obtained with solution (1) is not more intense than the spot in the chromatogram obtained with solution (2) and not more than one such spot is more intense than the spot in the chromatogram obtained with solution (3).
ASSAY
Carry out the following procedure protected from light. Dilute a suitable volume with sufficient 0.1M hydrochloric acid to produce a solution containing 0.0005% w/v of Chlorpromazine Hydrochloride and measure the absorbance at the maximum at 254 nm, Appendix II B. Calculate the content of C17H19ClN2S,HCl taking 915 as the value of A(1%, 1 cm) at the maximum at 254 nm.
STORAGE
Chlorpromazine Injection should be protected from light.
