สารบัญ

Category Antibacterial (ophthalmic).

          Chloramphenicol Eye Drops are a sterile, buffered solution of Chloramphenicol. They contain not less than 90.0 per cent and not more than 130.0 per cent of the labelled amount of C₁₁H₁₂Cl₂N₂O₅.

Strength available 0.5 per cent w/v.

Dose Topical, to the conjunctiva, 1 drop every 1 to 4 hours.

Contra-indication It is contra-indicated in patients with a history of toxic reaction to chloramphenicol.

Precaution
          1. Long-term use of chloramphenicol ophthalmic preparation may cause bone marrow hypoplasia.
          2. If superinfection occurs during chloramphenicol therapy, the drug should be discontinued and appropriate therapy instituted.

Additional information Therapy should be continued for at least 48 hours after the eye appears normal.

Packaging and storage Chloramphenicol Eye Drops shall be kept in tightly closed containers, protected from light, stored at a temperature between 2^º and 8^º and not be frozen.

Identification
          A. To a volume containing 50 mg of chloramphenicol, add 15 ml of water and extract with four 25-ml portions of ether. Combine the extracts and evaporate to dryness. The dried residue complies with the test for Identification A described under Chloramphenicol Capsules, p. 64.
          B. 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.

pH 7.0 to 7.5, except in case of Eye Drops that is unbuffered the pH is 3.0 to 6.0 (Appendix 4.15).

2-Amino-1-(4-nitrophenyl)propane-1,3-diol Carry out the test as described in the “High-Pressure Liquid Chromatography” (Appendix 3.5).

          Mobile phase Mix 85 volumes of a 0.21 per cent w/v solution of sodium pentanesulfonate, 15 volumes of acetonitrile and 1 volume of glacial acetic acid.
          Standard solution Prepare a solution containing 0.0040 per cent w/v of 2-Amino-1-(4-nitrophenyl) propane-1,3-diol RS in Mobile phase.
         Test solution Dilute the eye drops with Mobile phase to contain 0.050 per cent w/v of chloramphenicol.
          Chromatographic system The chromatographic procedure may be carried out using (a) a stainless steel column (10 cm × 4.6 mm) packed with octadecylsilane chemically bonded to silica gel (5 μm) (Nucleosil C 18 or equivalent is suitable), (b) Mobile phase at a flow rate of 2 ml per minute, and (c) an ultraviolet photometer set at 272 nm.
          Procedure Separately inject equal volumes of Standard solution and Test solution into the chromatograph, record the chromatograms, and measure the responses for the major peaks.
          In the chromatogram obtained from the test solution the area of any peak corresponding to 2-amino-1-(4 nitrophenyl)propane-1,3-diol is not more than the area of the peak in the chromatogram obtained from the standard solution.

Assay Carry out the determination as described in the “High-pressure Liquid Chromatography” (Appendix 3.5).
          Mobile phase; Chromatographic system and Procedure Proceed as directed in the Assay under Chloramphenicol, p. 64.
          Standard preparation Dissolve an accurately weighed quantity of Chloramphenicol RS in Mobile phase, and dilute quantitatively, and stepwise if necessary, with Mobile phase to obtain a solution having a known concentration of about 100 μg per ml.
          Assay preparation Transfer an accurately measured volume of Chloramphenicol Eye Drops, containing about 50 mg of chloramphenicol, to a 100-ml volumetric flask, dilute with Mobile phase to volume, and mix. Transfer 5.0 ml of the resulting solution to a 25-ml volumetric flask, dilute with Mobile phase to volume, and mix.
          Calculation Calculate the content of C₁₁H₁₂Cl₂N₂O₅ in the portion of the Eye Drops taken, using the declared content of C₁₁H₁₂Cl₂N₂O₅ in Chloramphenicol RS.

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