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Doxycycline for Oral Suspension
» Doxycycline for Oral Suspension contains the equivalent of not less than 90.0 percent and not more than 125.0 percent of the labeled amount of C22H24N2O8 when constituted as directed. It contains one or more suitable buffers, colors, diluents, flavors, and preservatives.
Packaging and storage— Preserve in tight, light-resistant containers.
Identification— To a quantity of Doxycycline for Oral Suspension (powder), equivalent to about 50 mg of doxycycline, add 50 mL of methanol, shake, and allow to settle. Using the clear supernatant as the Test Solution, proceed as directed for Method II under Identification—Tetracyclines 193.
Uniformity of dosage units 905—
FOR SOLID PACKAGED IN SINGLE-UNIT CONTAINERS: meets the requirements.
Deliverable volume 698: meets the requirements.
pH 791: between 5.0 and 6.5, in the suspension constituted as directed in the labeling.
Water, Method I 921: not more than 3.0%.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Assay—
Mobile phase, Diluent, Resolution solution, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Doxycycline Hyclate.
Assay preparation— Constitute Doxycycline for Oral Suspension as directed in the labeling. Transfer an accurately measured portion of the constituted suspension, freshly mixed and free from air bubbles, equivalent to about 100 mg of doxycycline, to a 100-mL volumetric flask, add 50 mL of 0.1 N hydrochloric acid, and shake by mechanical means for about 15 minutes. Dilute with Diluent to volume, and mix. Filter through filter paper, discarding the first 10 mL of the filtrate, then filter through a filter of 0.5-µm or finer porosity.
Procedure— Proceed as directed for Procedure in the Assay under Doxycycline Hyclate. Calculate the quantity, in mg of doxycycline (C22H24N2O8), in each mL of the constituted suspension taken by the formula:
0.1(CP / V)(rU / rS),
in which V is the volume, in mL, of the constituted suspension taken to prepare the Assay preparation, and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 763
Phone Number : 1-301-816-8223