Baclofen Oral Suspension
Baclofen Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled amount of baclofen (C10H12ClNO2).
Prepare Baclofen Oral Suspension 5 mg/mL as follows (see Pharmaceutical CompoundingNonsterile Preparations 795).
If using Baclofen Tablets, place the Tablets in a suitable mortar and comminute to a fine powder, or add Baclofen powder. Add 5 mL of the Vehicle to wet the powder, and triturate the powder to form a fine paste. Add the Vehicle in small portions almost to volume, and mix thoroughly after each addition. Transfer, stepwise and quantitatively, the contents of the mortar to a calibrated bottle. Add sufficient Vehicle to bring to final volume, and mix well.
Mobile phase: Acetonitrile and 0.05 M monobasic sodium phosphate (20:80). Adjust with phosphoric acid to a pH of 3.5.
Standard solution: 5 µg/mL of USP Baclofen RS in water
Sample solution: Shake thoroughly by hand each bottle of Oral Suspension. Pipet 0.5 mL of Oral Suspension from each bottle to a 500-mL volumetric flask, dilute with water to volume to obtain a concentration of 5 µg/mL, and pass through a 0.22-µm polyvinylidenefluoride (PVDF) filter.
Detector: UV 220 nm
Column: 4.6-mm × 25-cm; 5-µm packing L1
Flow rate: 1 mL/min
Injection size: 15 µL
Sample: Standard solution
[NoteThe retention time of baclofen is about 5.5 min. ]
Relative standard deviation: NMT 2.0% for replicate injections
Samples: Standard solution and Sample solution
Calculate the percentage of the labeled amount of baclofen (C10H12ClNO2) in the portion of Oral Suspension taken:
Result = (rU/rS) × (CS/CU) × 100
Acceptance criteria: 90.0%110.0%
• pH 791: 4.25.2
• Packaging and Storage: Package in tight, light-resistant containers. Store in a cold place.
• Labeling: Label it to state that it is to be well shaken, and to state the Beyond-Use Date.
• Beyond-Use Date: NMT 35 days after the day on which it was compounded
• USP Reference Standards 11
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USP35NF30 Page 2300Pharmacopeial Forum: Volume No. 32(1) Page 51