Which drug is the Rho kinase inhibitor?

• A. Netarsudil
• B. Latanoprost
• C. Dorzolamide
• D. Prednisolone

Answer: (A)

Rho kinase inhibitors work by blocking the RhoA-ROCK signaling pathway in the trabecular meshwork, which reduces cell contractility and relaxes the outflow pathways, increasing aqueous humor drainage and lowering intraocular pressure. Netarsudil is the drug that fits this mechanism, as it directly inhibits ROCK to enhance conventional outflow and can also lower intraocular pressure by reducing episcleral venous pressure. Latanoprost is a prostaglandin analog that increases uveoscleral outflow, dorzolamide inhibits carbonic anhydrase to decrease aqueous humor production, and prednisolone is a corticosteroid that can raise IOP in steroid responders—so none of them perform the ROCK-inhibition action.