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Published on: August 9, 2022
Reformulation of a codeine phosphate liquid controlled-release product.
Eva Roblegg1, Peter Dittrich, Krista Haltmeyer
1Department of Pharmaceutical Technology, Institute of Pharmaceutical Sciences, Karl-Franzens University of Graz, Graz, Austria. eva.roblegg@uni-graz.at
New ion-exchange resins offer a viable alternative for developing stable, controlled-release codeine formulations without Eudragit coating. These resins provide effective drug release and maintain stability for at least six months.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
Background:
- Ion-exchange resins are utilized in drug formulations for controlled release, improved swallowability, stability, and taste-masking.
- Modern manufacturing regulations necessitate alternatives to Eudragit coating in delayed-release preparations.
Purpose of the Study:
- To evaluate new ion-exchange resins as replacements for existing ones in codeine formulations.
- To achieve beneficial formulation properties without Eudragit coating.
Main Methods:
- Nine cationic exchangers were loaded with codeine.
- In vitro codeine release profiles were assessed using the USP XXIII paddle method.
Main Results:
- Amberlite IR 69 F and Dowex 50 × 8-100 showed the most favorable release profiles.
- Formulated drug-resin complexes (cough syrup and concentrate) demonstrated equivalent release profiles to the non-formulated complex.
- Stability of release profiles, free codeine levels, purity, and identity were maintained for over six months.
Conclusions:
- Ion exchangers are highly suitable for developing sustained-release codeine formulations.
- The evaluated resins offer a promising alternative for codeine formulation development.
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