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Category Antifungal.

      Griseofulvin Tablets contain not less than 90.0 per cent and not more than 115.0 per cent of the labelled amount of C₁₇H₁₇ClO₆.

Strengths available 125, 250 and 500 mg.

Dose Adults: 500 mg to 1 g daily in single or divided doses.

      Children: 10 mg per kg of body weight daily in single or divided doses.

Contra-indication; Warning See under Griseofulvin, p. 115.

Precaution If fever, sore throat or skin rash occurs, notify the physician.

      See also under Griseofulvin, p. 115.

Additional information

      1. It should be taken with or after meals or milk, preferably taken after fatty meals to increase absorption.

      2. Griseofulvin may be available in ultramicrosize form (less than 1 μm in diameter). The dose should be reduced accordingly.

Packaging and storage Griseofulvin Tablets shall be kept in tightly closed containers.

Labelling The label on the container states that griseofulvin is in microsize form.

Identification

      A. The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.

      B. Dissolve 5 mg of the tablet contents in 1 ml of sulfuric acid and add 5 mg of powdered potassium dichromate: a red colour is produced.

Dissolution Carry out the test as described in the “Dissolution Test” (Appendix 4.24).

      Dissolution medium: water containing 40.0 mg of sodium dodecyl sulfate per ml; 1000 ml. 

      Apparatus 2: 75 rpm.

      Time: 90 minutes.

      Procedure Determine the amount of C₁₇H₁₇ClO₆ dissolved from absorbances at about 291 nm of filtered portions of the test solution, suitably diluted with a mixture of 4 volumes of methanol and 1 volume of water, if necessary, in comparison with a standard solution having a known concentration of Griseofulvin RS in the same medium (Appendix 2.2).

      Tolerances Not less than 75 per cent (Q) of the labelled amount of C₁₇H₁₇ClO₆ is dissolved in 90 minutes.

Loss on drying Not more than 5.0 per cent w/w after drying about 100 mg of finely ground tablets, accurately weighed, in a capillary-stoppered bottle in vacuum at a pressure not exceeding 0.7 kPa (about 5 Torr) at 60º for 3 hours (Appendix 4.15). 

Assay Carry out the determination as described in the “High-pressure Liquid Chromatography” (Appendix 3.5).

Mobile phase, Standard preparation, Chromatographic system, and Procedure Proceed as directed in the Assay under Griseofulvin, p. 116.

Assay preparation Weigh and finely powder not less than 20 Griseofulvin Tablets. Transfer an accurately weighed portion of the powder, containing about 125 mg of griseofulvin, to a 100-ml volumetric flask. Add about 70 ml of methanol, shake by mechanical means for 30 minutes, and dilute with methanol to volume. Mix and filter. Transfer 5.0 ml of the clear filtrate to a 50-ml volumetric flask, dilute with Mobile phase to volume, and mix. 

Calculation Calculate the content of C₁₇H₁₇ClO₆ in the portion of the Tablets taken, using the declared content of C₁₇H₁₇ClO₆ in Griseofulvin RS.

Other requirements Comply with the requirements described under “Tablets” (Appendix 1.16).