Page 108 - Pharmaceutics IV (02-06-01305)
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Ophthalmic DD: routes & pharmacokinetics
Fate of topically delivered drugs
Noncorneal, nonproductive absorption and precorneal drainage
• A number of factors can influence nasolacrimal drainage
• Higher viscosity thickens the tear film,
Viscosity decreases drainage, prolongs precorneal
residence & increases ocular absorption
• Viscosity limit & painful sensation!
Occlusion of the • Controls drainage, prolongs precorneal
nasolacrimal duct residence & increases ocular absorption
209
Ophthalmic DD: routes & pharmacokinetics
Fate of topically delivered drugs
210 105
Salma E. EL-Habashy
