Promazine Tablets
Action and use
Dopamine receptor antagonist; neuroleptic.
Definition
Promazine Tablets contain Promazine Hydrochloride. They are coated.
Content of promazine hydrochloride, C17H20N2S,HCl
92.5 to 107.5% of the stated amount.
Identification
Related substances
Comply with the test for related substances in phenothiazines, Appendix III A, using mobile phase A and the following freshly prepared solutions. For solution (1) extract a quantity of the powdered tablets containing 0.1 g of Promazine Hydrochloride with 10 mL of methanol and filter. For solution (2) dilute 1 volume of solution (1) to 200 volumes with methanol.
Assay
Carry out the following procedure protected from light. Weigh and powder 20 tablets. Triturate a quantity of the powder containing 50 mg of Promazine Hydrochloride with 10 mL of 2m hydrochloric acid and then add 200 mL of water. Shake for 15 minutes, add sufficient water to produce 500 mL and centrifuge about 50 mL of the mixture. To 5 mL of the clear, supernatant liquid add 10 mL of 0.1m hydrochloric acid and sufficient water to produce 100 mL. Measure the absorbance of the resulting solution at the maximum at 251 nm, Appendix II B. Calculate the content of C17H20N2S,HCl taking 935 as the value of A(1%, 1 cm) at the maximum at 251 nm.