Carbinoxamine Maleate Tablets

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

DOWNLOAD PDF HERE

1 DEFINITION

Carbinoxamine Maleate Tablets contain NLT 93.0% and NMT 107.0% of the labeled amount of carbinoxamine maleate (C₁₆H₁₉ClN₂O · C₄H₄O₄).

2 IDENTIFICATION

Delete the following:

A.Standard solution: 0.02 mg/mL of USP Carbinoxamine Maleate RS in dilute sulfuric acid (1 in 70)

Sample solution: Nominally 0.02 mg/mL of carbinoxamine maleate in dilute sulfuric acid (1 in 70), from the Tablets, as directed under Salts of Organic Nitrogenous Bases 〈501〉.

Analytical wavelength: 263 ± 2 nm

Acceptance criteria: The absorptivity of the Sample solution at 263 nm is within 7.0% of that of the Standard solution. 2S (USP41)

Add the following:

A. The UV spectrum of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.2S(USP41)

Add the following:

B. The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.2S (USP41)

3 ASSAY

Change to read:

Procedure

Solution A: 2.72 g/L of monobasic potassium phosphate. Adjust with phosphoric acid to a pH of 4.0.

Solution B: Methanol and acetonitrile (80:20)

Mobile phase: See Table 1.

Table 1

Diluent 1: 0.1 N hydrochloric acid

Diluent 2: Methanol, acetonitrile, and water (200:50:750)

System suitability solution: 0.1 mg/mL of USP Carbinoxamine Maleate RS and 0.01 mg/mL each of USP Carbinoxamine Related Compound

A RS and USP Carbinoxamine Related Compound B RS in Diluent 2

Standard solution: 0.1 mg/mL of USP Carbinoxamine Maleate RS in Diluent 2

Sample solution: Nominally 0.1 mg/mL of carbinoxamine maleate prepared as follows. Transfer a suitable amount of powder from finely powdered Tablets (NLT 20) to a suitable volumetric flask. Add 70% of the flask volume of Diluent 1 and shake for 15 min, then dilute with Diluent 2 to volume. Centrifuge the solution and filter the supernatant by passing through a suitable filter of 0.45-μm pore size, discarding the first 2–3 mL of filtrate. Inject the freshly prepared solution immediately.

Chromatographic system

(See Chromatography 〈621〉, System Suitability.)

Mode: LC

Detector: UV 225 nm. For Identification A , use a diode array detector in the range of 200–400 nm.

Column: 4.6-mm × 15-cm; 5-μm packing L7

Column temperature: 40°

Flow rate: 1 mL/min

Injection volume: 10 μL

System suitability

Samples: System suitability solution and Standard solution

[Note—See Table 2 for relative retention times.]

Suitability requirements

Resolution: NLT 4.0 between carbinoxamine related compound A and carbinoxamine related compound B, System suitability solution

Tailing factor: NMT 1.5, Standard solution

Relative standard deviation: NMT 1.0%, Standard solution

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of the labeled amount of carbinoxamine maleate (C₁₆H₁₉ClN₂O · C₄H₄O₄) in the portion of Tablets taken:

Result = (r_U/r_S) x (C_S/C_U) × 100

r_U = peak response of carbinoxamine from the Sample solution

r_S = peak response of carbinoxamine from the Standard solution

C_S = concentration of USP Carbinoxamine Maleate RS in the Standard solution (mg/mL)

C_U = nominal concentration of carbinoxamine maleate in the Sample solution (mg/mL) 2S (USP41)

Acceptance criteria: 93.0%–107.0%

4 PERFORMANCE TESTS

Change to read:

Dissolution 〈711〉

Medium: Water; 900 mL

Apparatus 2: 50 rpm

Time: 45 min

Standard solution: USP Carbinoxamine Maleate RS in Medium with a concentration similar to that expected in the Sample solution

Sample solution: Filter a portion of the solution under test and dilute with Medium as needed.

Instrumental conditions

Mode: UV

Analytical wavelength: Maximum absorbance at about 260 nm

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of the labeled amount of carbinoxamine maleate (C₁₆H₁₉ClN₂O · C₄H₄O₄) dissolved:

Result = (A_U/A_S ) × C_S × V × D × (1/L) × 100

A_U = absorbance from the Sample solution

A_S = absorbance of carbinoxamine maleate from the Standard solution

C_S = concentration of USP Carbinoxamine Maleate RS in the Standard solution (mg/mL)

V = volume of Medium, 900 mL

D = dilution factor for the Sample solution

L = label claim (mg/Tablet) 2S (USP41)

Tolerances: NLT 75% (Q) of the labeled amount of carbinoxamine maleate (C₁₆H₁₉ClN₂O · C₄H₄O₄) is dissolved.

Change to read:

Uniformity of Dosage Units 〈905〉: Meet the requirements2S (USP41)

5 IMPURITIES

Change to read:

Organic Impurities

Solution A, Solution B, Mobile phase, Diluent 1, Diluent 2, and System suitability solution: Prepare as directed in the Assay.

Standard stock solution: 0.028 mg/mL of USP Carbinoxamine Maleate RS (equivalent to 0.02 mg/mL of carbinoxamine) (ERR 1-Mar-2019)

and 0.02 mg/mL each of USP Carbinoxamine Related Compound A RS and USP Carbinoxamine Related Compound B RS in Diluent 2

Standard solution: 0.0014 mg/mL of USP Carbinoxamine Maleate RS (equivalent to 0.001 mg/mL of carbinoxamine) (ERR 1-Mar-2019) and

0.001 mg/mL each of USP Carbinoxamine Related Compound A RS and USP Carbinoxamine Related Compound B RS in Diluent 2, from

Standard stock solution

Sample solution: Nominally 1.0 mg/mL of carbinoxamine maleate prepared as follows. Transfer a suitable quantity of powder from finely powdered Tablets (NLT 20) to a suitable volumetric flask. Add 75% of the flask volume of Diluent 1, shake for 15 min, and dilute with Diluent 2 to volume. Centrifuge the solution and filter the supernatant by passing through a suitable filter of 0.45-μm pore size, discarding the first 2–3 mL of filtrate. Inject the freshly prepared solution immediately.

Chromatographic system

(See Chromatography 〈621〉, System Suitability.)

Mode: LC

Detector: UV 225 nm

Column: 4.6-mm × 15-cm; 5-μm packing L7

Column temperature: 40°

Flow rate: 1 mL/min

Injection volume: 10 μL

System suitability

Samples: System suitability solution and Standard solution

[Note—See Table 2 for relative retention times.]

Suitability requirements

Resolution: NLT 4.0 between carbinoxamine related compound A and carbinoxamine related compound B, System suitability solution

Relative standard deviation: NMT 5.0% for each corresponding compound present in the Standard solution

Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of carbinoxamine related compound A and carbinoxamine related compound B in the portion of Tablets taken:

Result = (r_U/r_S) x (C_S/C_U ) × 100

r_U = peak response of carbinoxamine related compound A or carbinoxamine related compound B from the Sample solution

r_S = peak response of the corresponding Reference Standard from the Standard solution

C_S = concentration of the corresponding Reference Standard in the Standard solution (mg/mL)

C_U = nominal concentration of carbinoxamine maleate in the Sample solution (mg/mL)

Calculate the percentage of each unspecified degradation product in the portion of Tablets taken:

Result = (r_U/r_S) x (C_S/C_U ) × 100

r_U = peak response of each unspecified degradation product from the Sample solution

r_S = peak response of carbinoxamine from the Standard solution

C_S = concentration of USP Carbinoxamine Maleate RS(as the free base) (ERR 1-Mar-2019) in the Standard solution (mg/mL)

C_U = nominal concentration of carbinoxamine maleate in the Sample solution (mg/mL)

Acceptance criteria: See Table 2. The reporting threshold is 0.05%.

Table 2

^a Process impurity included for identification only and not included in the calculation of total degradation products.

^b N,N-Dimethyl-2-[phenyl(pyridin-2-yl)methoxy]ethan-1-amine. 2S (USP41)

6 ADDITIONAL REQUIREMENTS

Change to read:

Packaging and Storage: Preserve in tight, light-resistant containers, and store at controlled room temperature.2S (USP41)

Change to read:

USP Reference Standards 〈11〉

USP Carbinoxamine Maleate RS

USP Carbinoxamine Related Compound A RS

(4-Chlorophenyl)(pyridin-2-yl)methanone.

C₁₂H₈ClNO 217.65

USP Carbinoxamine Related Compound B RS

(4-Chlorophenyl)(pyridin-2-yl)methanol.

C₁₂H₁₀ClNO 219.67 2S (USP41)