Alprazolam Oral Suspension
Alprazolam Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled amount of alprazolam (C17H13ClN4).
Prepare Alprazolam Oral Suspension 1 mg/mL as follows (see Pharmaceutical Compounding—Nonsterile Solutions 795).
Alprazolam 100 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
Comminute tablets in a suitable mortar to a fine powder, or add Alprazolam powder. Add about 20 mL of the Vehicle, and mix to a uniform paste. Add the Vehicle in small portions almost to volume, and mix thoroughly after each addition. Transfer the contents of the mortar, stepwise and quantitatively, to a calibrated bottle. Add sufficient Vehicle to bring to final volume, and mix well.
•  Procedure
Buffer:  0.04 M sodium acetate solution. Adjust with glacial acetic acid to a pH of 2.4.
Mobile phase:  Methanol, acetonitrile, and Buffer (45:8:47)
Standard solution:  20 µg/mL of USP Alprazolam RS in Mobile phase
Sample solution:  Agitate the container of Oral Suspension for 30 min on a rotating mixer, remove a 5-mL sample, and store in a clear glass vial at 70 until analyzed. At the time of analysis, remove the sample from the freezer, allow it to reach room temperature, and mix with a vortex mixer for 30 s. Dilute a suitable volume of the Oral Suspension in Mobile phase to obtain a nominal concentration of 20 µg/mL.
Chromatographic system 
Mode:  LC
Detector:  UV 230 nm
Column:  4.6-mm × 25-cm; 5-µm packing L1
Flow rate:  0.6 mL/min
Injection size:  20 µL
System suitability 
Sample:  Standard solution
[Note—The retention time of alprazolam is about 10 min. ]
Suitability requirements 
Relative standard deviation:  NMT 1.4% for replicate injections
Samples:  Standard solution and Sample solution
Calculate the percentage of the labeled amount of alprazolam (C17H13ClN4) 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 alprazolam in the Standard solution (µg/mL)
CU== nominal concentration of alprazolam in the Sample solution (µg/mL)
Acceptance criteria:  90.0%–110.0%
•  pH 791: 4.0–5.0
•  Packaging and Storage: Package in tight, light-resistant containers. Store at controlled room temperature, or under refrigeration.
•  Labeling: Label it to state that it is to be well-shaken before use, and to state the Beyond-Use Date.
Beyond-Use Date:  NMT 60 days after the day on which it was compounded
•  USP Reference Standards 11
USP Alprazolam RS Click to View Structure
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
(CMP2010) Compounding
Reference Standards RS Technical Services
USP35–NF30 Page 2103
Pharmacopeial Forum: Volume No. 32(1) Page 46