Anti glaucoma drug that act by increasing uvea scleral outflow is?
**Core Concept**
The question is testing the student's knowledge of the mechanism of action of anti-glaucoma medications, specifically those that increase uveoscleral outflow. Uveoscleral outflow is one of the two main pathways for aqueous humor drainage from the eye, the other being trabecular meshwork outflow. Increasing uveoscleral outflow is a therapeutic strategy to reduce intraocular pressure (IOP) in glaucoma patients.
**Why the Correct Answer is Right**
Latanoprost is a prostaglandin F2Ξ± analogue that acts by increasing uveoscleral outflow, thereby reducing IOP. This is achieved by stimulating the prostaglandin F2Ξ± receptor (FP receptor) in the ciliary body, which leads to relaxation of the ciliary muscle and opening of the uveoscleral pathway. The increased outflow of aqueous humor results in a decrease in IOP. Latanoprost is a first-line treatment for glaucoma and has a proven efficacy in reducing IOP.
**Why Each Wrong Option is Incorrect**
**Option B:** Timolol is a non-selective beta-blocker that acts by reducing aqueous humor production, not by increasing uveoscleral outflow. It is used to decrease IOP in glaucoma patients by reducing the production of aqueous humor in the ciliary body.
**Option C:** Pilocarpine is a muscarinic receptor agonist that acts by increasing trabecular meshwork outflow, not uveoscleral outflow. It is used to decrease IOP in glaucoma patients by increasing the outflow of aqueous humor through the trabecular meshwork.
**Option D:** Dorzolamide is a carbonic anhydrase inhibitor that acts by reducing aqueous humor production, not by increasing uveoscleral outflow. It is used to decrease IOP in glaucoma patients by reducing the production of aqueous humor in the ciliary body.
**Clinical Pearl / High-Yield Fact**
It is essential to differentiate between the various anti-glaucoma medications based on their mechanism of action to choose the most appropriate treatment for a patient. Understanding the different pathways of aqueous humor drainage is crucial in selecting the right medication to increase uveoscleral outflow.
**β Correct Answer: A. Latanoprost**