Latanoprost ethyl amide (Lat-NEt) is a latanoprost analog in which the C-1 carboxyl group has been modified to an N-ethyl amide. Prostaglandin esters exhibit ocular hypotensive activity, and prostaglandin N-ethyl amides have recently been introduced as alternative ocular hypotensive prodrugs. Although it has been claimed that prostaglandin ethyl amides are not converted to free acids in vivo, studies in our laboratories show that bovine and human corneal tissue can convert the N-ethyl amides of various prostaglandins to free acids at a rate of about 2.5 μg/g corneal tissue/hr. Lat-NEt is expected to exhibit the typical intraocular effects of latanoprost free acid, but with much slower hydrolysis pharmacokinetics characteristic of prostaglandin N-amides.