Related Experiment Videos
Topically applied pilocarpine. Human pupillary response as a function of drop size
Archives of Ophthalmology (Chicago, Ill. : 1960)
|January 1, 1980
Summary
Reducing ophthalmic drug volume, such as pilocarpine hydrochloride, significantly enhances ocular absorption in humans. Lower volumes, like 20 microL, yield similar miotic responses to larger volumes, indicating reduced waste.
Area of Science:
- Ophthalmology
- Pharmacokinetics
- Drug Delivery
Background:
- Topical ophthalmic drug absorption is crucial for ocular treatment efficacy.
- Animal models suggest decreased instillation volume increases ocular drug absorption.
- Human confirmation of this principle for ophthalmic drugs is lacking.
Purpose of the Study:
- To investigate the effect of reduced topical ophthalmic drug volume on ocular absorption in humans.
- To compare the miotic response to different volumes of pilocarpine hydrochloride in human volunteers.
Main Methods:
- Ten adult human volunteers participated in the study.
- A 0.5% pilocarpine hydrochloride solution was administered in two volumes: 20 microL and 50 microL.
- The miotic response (pupil constriction) was measured and compared between the two dose volumes.
Main Results:
- A 20-microL dose of pilocarpine hydrochloride produced a miotic response essentially equivalent to a 50-microL dose.
- This indicates that a substantial reduction in instilled volume did not compromise the therapeutic effect.
- Findings suggest significant drainage loss of topical ophthalmic drugs with standard dropper volumes.
Conclusions:
- Lowering the volume of topically applied ophthalmic drugs can enhance ocular absorption and maintain therapeutic efficacy in humans.
- Current commercial dropper volumes may exceed the optimal amount needed for desired ocular response, leading to drug wastage.
- These results have implications for optimizing ophthalmic drug dosing and formulation strategies.