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Published on: March 11, 2017
Comparative analysis of prednisolone acetate suspensions.
Calvin W Roberts1, Peter L Nelson
1Department of Ophthalmology, Weill Medical College of Cornell University, New York, NY 10021, USA. robertsmd@aol.com
Summary
Prednisolone acetate particles in Pred Forte suspensions were smaller and more uniform, leading to longer suspension times. This suggests improved dose homogeneity and ocular bioavailability compared to other formulations.
Area of Science:
- Ophthalmology
- Pharmaceutics
- Materials Science
Background:
- Prednisolone acetate is a corticosteroid commonly used in ophthalmic suspensions.
- Particle size and uniformity significantly impact the stability and efficacy of suspensions.
- Variations in particle characteristics can lead to differences in sedimentation, homogeneity, and bioavailability.
Purpose of the Study:
- To compare particle size differences among three prednisolone acetate ophthalmic suspensions: Pred Forte, EconoPred Plus, and a generic 1% formulation.
- To evaluate the impact of particle size on sedimentation and stability over time.
Main Methods:
- Laboratory evaluation of three prednisolone acetate suspensions.
- Qualitative assessment of sedimentation rate based on particle size.
- Sampling from the top of suspensions at 0, 6, 12, 24, 36, 48, 60, and 72 hours.
- Sampling from the bottom of suspensions at 72 hours.
Main Results:
- Particle size of aliquots from the top of all suspensions decreased over time.
- Pred Forte samples at 72 hours (bottom) were consistent with initial (T=0h) results.
- Generic and EconoPred Plus samples showed increased particle size at 72 hours (bottom) compared to T=0h, indicating greater agglomeration.
Conclusions:
- Prednisolone particles in Pred Forte suspensions are smaller and more uniform.
- This uniformity allows Pred Forte particles to remain suspended for longer durations.
- Improved suspension stability may lead to enhanced dose homogeneity and ocular bioavailability.
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