AAPS PharmSciTech

, 10:808 | Cite as

Nanoemulsion as a Potential Ophthalmic Delivery System for Dorzolamide Hydrochloride

  • Hussein O. AmmarEmail author
  • H. A. Salama
  • M. Ghorab
  • A. A. Mahmoud
Research Article


Dilutable nanoemulsions are potent drug delivery vehicles for ophthalmic use due to their numerous advantages as sustained effect and high ability of drug penetration into the deeper layers of the ocular structure and the aqueous humor. The aim of this article was to formulate the antiglaucoma drug dorzolamide hydrochloride as ocular nanoemulsion of high therapeutic efficacy and prolonged effect. Thirty-six systems consisting of different oils, surfactants, and cosurfactants were prepared and their pseudoternary-phase diagrams were constructed by water titration method. Seventeen dorzolamide hydrochloride nanoemulsions were prepared and evaluated for their physicochemical and drug release properties. These nanoemulsions showed acceptable physicochemical properties and exhibited slow drug release. Draize rabbit eye irritation test and histological examination were carried out for those preparations exhibiting superior properties and revealed that they were nonirritant. Biological evaluation of dorzolamide hydrochloride nanoemulsions on normotensive albino rabbits indicated that these products had higher therapeutic efficacy, faster onset of action, and prolonged effect relative to either drug solution or the market product. Formulation of dorzolamide hydrochloride in a nanoemulsion form offers, thus, a more intensive treatment of glaucoma, a decrease in the number of applications per day, and a better patient compliance compared to conventional eye drops.

Key words

dorzolamide hydrochloride glaucoma nanoemulsion pharmacodynamic physicochemical characterization 



We gratefully appreciate the generous supply of dorzolamide hydrochloride by Jamjoom Pharma, Jeddah, KSA and the kind help for assessment of the ocular irritation test by Dr. Maali A. Halim, Faculty of Medicine, Cairo University. We also acknowledge the financial support provided by the National Research Center, Egypt.


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Copyright information

© American Association of Pharmaceutical Scientists 2009

Authors and Affiliations

  • Hussein O. Ammar
    • 1
    Email author
  • H. A. Salama
    • 1
  • M. Ghorab
    • 2
  • A. A. Mahmoud
    • 1
  1. 1.Department of Pharmaceutical TechnologyNational Research CenterCairoEgypt
  2. 2.Department of Pharmaceutics, Faculty of PharmacyCairo UniversityCairoEgypt

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