Stability and uniformity of extemporaneous preparations of voriconazole in two liquid suspension vehicles at two storage temperatures.
OBJECTIVE
To determine the stability and distribution of voriconazole in 2 extemporaneously prepared (compounded) suspensions stored for 30 days at 2 temperatures.


METHODS
Voriconazole suspensions (40 mg/mL) compounded from commercially available 200-mg tablets suspended in 1 of 2 vehicles. One vehicle contained a commercially available suspending agent and a sweetening syrup in a 1:1 mixture (SASS). The other vehicle contained the suspending agent with deionized water in a 3:1 mixture (SADI).


METHODS
Voriconazole suspensions (40 mg/mL in 40-mL volumes) were compounded on day 0 and stored at room temperature (approx 21 degrees C) or refrigerated (approx 5 degrees C). To evaluate distribution, room-temperature aliquots of voriconazole were measured immediately after preparation. Refrigerated aliquots were measured after 3 hours of refrigeration. To evaluate stability, aliquots from each suspension were measured at approximately 7-day intervals for up to 30 days. Voriconazole concentration, color, odor, opacity, and pH were measured, and aerobic and anaerobic bacterial cultures were performed at various points.


RESULTS
Drug distribution was uniform (coefficient of variation, < 5%) in both suspensions. On day 0, 87.8% to 93.0% of voriconazole was recovered; percentage recovery increased to between 95.1% and 100.8% by day 7. On subsequent days, up to day 30, percentage recovery was stable (> 90%) for all suspensions. The pH of each suspension did not differ significantly throughout the 30-day period. Storage temperature did not affect drug concentrations at any time, nor was bacterial growth obtained.


CONCLUSIONS
Extemporaneously prepared voriconazole in SASS and SADI resulted in suspensions that remained stable for at least 30 days. Refrigerated versus room-temperature storage of the suspensions had no effect on drug stability.
Nguyen
Kyvan Q
KQ
Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Hawkins
Michelle G
MG
Taylor
Ian T
IT
Wiebe
Valerie J
VJ
Tell
Lisa A
LA
D000935:Antifungal Agents / Q000737:chemistry*; D004339:Drug Compounding / Q000662:veterinary*; D004355:Drug Stability; D014677:Pharmaceutical Vehicles; D011743:Pyrimidines / Q000737:chemistry*; D013535:Suspensions / Q000737:chemistry; D013607:Tablets; D013696:Temperature; D013997:Time Factors; D014230:Triazoles / Q000737:chemistry*; D065819:Voriconazole
D000935:Antifungal Agents; D014677:Pharmaceutical Vehicles; D011743:Pyrimidines; D013535:Suspensions; D013607:Tablets; D014230:Triazoles; D065819:Voriconazole