Provided is the use of a fatty acid or fatty acid ester, or a pharmaceutically acceptable salt or solvate thereof, selected from capric acid C10:0 monoglyceride, undecanoic acid C11:0, lauric acid C12:0, tridecanoic acid C13:0, myristic acid C14:0, pentadecylic acid C15:0, myristoleic acid C14:1cΔ9, palmitoleic acid C16:1cΔ9, oleic acid C18:1cΔ9, elaidic acid C18:1tΔ9, erucic acid C22:1cΔ13, linoleic acid C18:2cΔ9,12, linolenic acid C18:3cΔ9,12,15, lauric acid C12:0 monoglyceride, myristic acid C14:0 monoglyceride, ricinoleic acid, lauric acid C12:0 sodium salt, and myristic acid C14:0 sodium salt, for the treatment or prophylaxis of an infection of the eye caused by Neisseria gonorrhoeae in a warm-blooded animal, particularly in a newborn human. Also provided is an ophthalmic formulation comprising the fatty acid or ester, for example an eye drop liquid, an ointment or a hydrogel.
