Baclofen Oral Suspension
DEFINITION
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 Compounding—Nonsterile Preparations 
795
).
795).| Baclofen | 500 mg |
| Vehicle: a mixture of Vehicle for Oral Solution (regular or sugar-free), NF, and Vehicle for Oral Suspension, NF (1:1), a sufficient quantity to make | 100 mL |
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.
ASSAY
• Procedure
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.
Chromatographic system
Mode:
LC
Detector:
UV 220 nm
Column:
4.6-mm × 25-cm; 5-µm packing L1
Flow rate:
1 mL/min
Injection size:
15 µL
System suitability
Sample:
Standard solution
[Note—The retention time of baclofen is about 5.5 min. ]
Suitability requirements
Relative standard deviation:
NMT 2.0% for replicate injections
Analysis
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
| rU | = | = peak response from the Sample solution |
| rS | = | = peak response from the Standard solution |
| CS | = | = concentration of baclofen in the Standard solution (µg/mL) |
| CU | = | = nominal concentration of baclofen in the Sample solution (µg/mL) |
Acceptance criteria:
90.0%–110.0%
SPECIFIC TESTS
• pH 791:
4.2–5.2
791:
4.2–5.2
ADDITIONAL REQUIREMENTS
• 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
11
USP Baclofen RS 
') + '&img=../../images/v35300/cas-1134-47-0.gif',600,500);)
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
| Topic/Question | Contact | Expert Committee |
|---|---|---|
| Monograph | Jeanne H. Sun
Assistant Scientific Liaison 1-301-816-3361 |
(CMP2010) Compounding |
| Reference Standards | RS Technical Services 1-301-816-8129 rstech@usp.org |
USP35–NF30 Page 2300
Pharmacopeial Forum: Volume No. 32(1) Page 51