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PubMed · 2013850

Limits on optimizing ocular drug delivery.

J C Keister·E R Cooper·P J Missel·J C Lang·D F Hager
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Abstract

The problem of optimizing ocular bioavailability of topically applied ophthalmic drugs is discussed. A formula for drug concentration in the tear film is derived using well-known pharmacokinetic relationships and a first-order drug decay model for the tear film. The time integral of the tear film concentration is then related to ocular bioavailability. The results of this analysis show that: (1) high corneal permeability (corresponding to lipophilic compounds) produces the highest bioavailability; (2) the bioavailability of drugs with high corneal permeability is relatively unaffected by drug volume; and (3) by making the dosage volume sufficiently small, a bioavailability improvement factor of approximately 4 can be obtained for drugs with low corneal permeability.

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Administration, TopicalBiological AvailabilityCorneaHumansInstillation, DrugMathematicsModels, BiologicalOphthalmic SolutionsPermeabilityJournal Article

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J C Keister, E R Cooper, P J Missel, J C Lang, D F Hager. 1991. Limits on optimizing ocular drug delivery.. https://doi.org/10.1002/jps.2600800113

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PubMed2007

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