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Ophthalmic DD: dosage forms
Semisolid preparations
Ointments
• Requirements: must be free from large particles
265
Ophthalmic DD: dosage forms
Semisolid preparations
Gels
• Formulation concept: they are water-based semisolid systems
containing hydrophilic polymers dispersed in liquid (water).
Examples of polymers: polyvinyl alcohol (PVA), hydroxypropyl
methylcellulose (HPMC), …
• Advantages: they provide increased
contact time and increased drug
absorption.
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Salma E. EL-Habashy
