Carbamazepine Tablets
»Carbamazepine Tablets contain not less than 92.0percent and not more than 108.0percent of the labeled amount of C15H12N2O.
Packaging and storage— Preserve in tight containers,preferably of glass.Dispense Carbamazepine Tablets in a container labeled “Store in a dry place.Protect from moisture.”
Labeling— The labeling indicates the Dissolutiontest with which the product complies.
Identification— Boil,in a 50-mLbeaker,a quantity of powdered Tablets,equivalent to about 250mg of carbamazepine,with 15mLof acetone for 5minutes.Filter while hot into a second beaker,using two 5-mLportions of hot acetone to effect transfer.Evaporate with the aid of nitrogen to about 5mL,and cool in an ice bath until crystals are formed.Filter the crystals,wash with 3mLof cold acetone,and dry in vacuum at 70for 30minutes:the crystals so obtained respond to the Identificationtest under Carbamazepine.
Dissolution á711ñ—
FORPRODUCTS LABELED AS100-MG CHEWABLE TABLETS:
Test 1: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 1.
Medium: water containing 1%sodium lauryl sulfate;900mL.
Apparatus 2: 75rpm.
Time: 60minutes.
Procedure— Determine the amount of C15H12N2Odissolved from UVabsorbances at the wavelength of maximum absorbance at about 288nm of filtered portions of the solution under test,suitably diluted with Dissolution Medium,if necessary,in comparison with a Standard solution having a known concentration of USP Carbamazepine RSin the same medium.[NOTE—Avolume of methanol not exceeding 1%of the final total volume of the Standard solution may be used to dissolve the carbamazepine.]
Tolerances— Not less than 75%(Q)of the labeled amount of C15H12N2Ois dissolved in 60minutes.Use the Acceptance Table Table 1under Dissolution á711ñ,with the following exceptions:at S2,no unit is less than Q-5%;at S3,no unit is less than Q-10%;and not more than 2of the 24units are less than Q-5%.
Test 4: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 4.
Medium: 0.1Nhydrochloric acid containing 1%sodium lauryl sulfate;225mL.Add 2drops of simethicone to each.
Apparatus 3 (see Drug release á724ñ):35dips per minute;use 20-mesh screen on the top of the reciprocating cylinder and a 100-mesh screen on the bottom of the reciprocating cylinder.
Time: 60minutes.
Procedure— Determine the amount of C15H12N2Odissolved from UVabsorbances at the wavelength of maximum absorbance at about 284nm of filtered portions of the solution under test,suitably diluted with Dissolution Medium,if necessary,in comparison with a Standard solution having a known concentration of USP Carbamazepine RSin the same medium.
Tolerances— Not less than 70%(Q)of the labeled amount of C15H12N2Ois dissolved in 60minutes,the acceptance criteria specified for Test 1being used.
FORPRODUCTS LABELED AS200-MG TABLETS:
Test 2: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 2.
Medium ,Apparatus,and Procedure—Proceed as directed for Test 1.
Times and Tolerances—Between 45%and 75%of the labeled amount of C15H12N2Ois dissolved in 15minutes;not less than 75%(Q)of the labeled amount of C15H12N2Ois dissolved in 60minutes.Use Acceptance Table 1under Drug Release á724ñ,with the following exceptions:at 15minutes—at L2,no unit is more than 5%outside the stated range;at L3,no unit is more than 10%outside the stated range;and not more than 2of the 24units are more than 5%outside the stated range.At 60minutes—at L2,no unit is less than Q-5%;at L3,no unit is less than Q-10%;and not more than 2of the 24units are less than Q-5%.
Test 3: If the product complies with this test,the labeling indicates that it meets USPDissolution Test 3.
Medium ,Apparatus,and Procedure—Proceed as directed for Test 1.
Times and Tolerances—Between 60%and 85%of the labeled amount of C15H12N2Ois dissolved in 15minutes;not less than 75%(Q)of the labeled amount of C15H12N2Ois dissolved in 60minutes.Use Acceptance Table 1under Drug Release á724ñ,with the following exceptions:at 15minutes—at L2,no unit is more than 5%outside the stated range;at L3,no unit is more than 10%outside the stated range;and not more than 2of the 24units are more than 5%outside the stated range.At 60minutes—at L2,no unit is less than Q-5%;at L3,no unit is less than Q-10%;and not more than 2of the 24units are less than Q-5%.
Uniformity of dosage units á905ñ: meet the requirements.
Water,Method IIIá921ñ— Finely powder 20Tablets,and accurately weigh about 1.5g of the powder into a dry,tared evaporating dish.Dry at 120for 2hours:it loses not more than 5.0%of its weight.
Assay—
Mobile phase ,System suitability solution,Standard preparation,and Chromatographic system—Proceed as directed in the Assayunder Carbamazepine.
Assay preparation— Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 100mg of carbamazepine,to a 50-mLvolumetric flask,add about 40mLof methanol,sonicate for about 15minutes,allow to cool to room temperature,dilute with methanol to volume,mix,and filter,discarding the first 10mLof the filtrate.Transfer 5.0mLof this solution to a 50-mLvolumetric flask,dilute with a mixture of methanol and water (1:1)to volume,and mix.
Procedure— Proceed as directed in the Assayunder Carbamazepine.Calculate the quantity,in mg,of carbamazepine (C15H12N2O)in the portion of Tablets taken by the formula:
500C(rU/rS),
in which the terms are as defined therein.
Auxiliary Information— Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 342
Phone Number:1-301-816-8330