Allopurinol Oral Suspension
Allopurinol Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled amount of allopurinol (C5H4N4O).
Prepare Allopurinol Oral Suspension 20 mg/mL as follows (see Pharmaceutical Compounding—Nonsterile Preparations 795).
Allopurinol 2 g
Glycerin 5 mL
Vehicle for Oral Suspension, NF 45 mL
Vehicle for Oral Solution, NF, a sufficient quantity to make 100 mL
Select the number of tablets that contain the specified amount of allopurinol, and calculate the quantity of each ingredient required for the total amount to be prepared. Count, weigh, or measure each ingredient. Thoroughly pulverize the tablets. Mix the powdered Allopurinol tablets and Glycerin to form a smooth paste. Incorporate the Vehicle for Oral Suspension. Add sufficient Vehicle for Oral Solution to volume, and mix well. Adjust the pH, if necessary. Package and label.
•  pH 791: 6.5–7.5
•  Packaging and Storage: Package in a tight container, and store at controlled room temperature.
•  Labeling: Label it to state that it is to be shaken well before use, and that it is to be discarded after 60 days. Label it to state that it is to be kept out of the reach of children. Label it to indicate the nominal content of allopurinol in the Oral Suspension.
•  Beyond-use Date: NMT 60 days after the date on which it was compounded
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
USP35–NF30 Page 2100
Pharmacopeial Forum: Volume No. 29(4) Page 1000