Because they live so close to the outside of the body, "Thelazia" is one of the few nematode infections which can be treated topically.

Topical treatment of livestock, dogs and cats with organophosphates (such as ecothiopate iodide or isofluorophate) and systemic treatment with anthelmintics (such as ivermectin, levamisole, and doramectin) are recommended by the Merck Veterinary Manual. Other sources have reported positive results treating dogs with moxidectin, imidacloprid, or milbemycin oxime.

For the treatment of human cases, removal of the worm is suggested. Topical treatment with cocaine or thiabendazole have also been reported to kill the worms in human cases.

Because most, if not all, species of "Thelazia" are spread by flies, sanitary practices which reduce the presence of flies will also reduce the spread of thelaziasis.

Thelaziasis (occasionally spelled "thelaziosis") is the term for infestation with parasitic nematodes of the genus "Thelazia". The adults of all "Thelazia" species discovered so far inhabit the eyes and associated tissues (such as eyelids, tear ducts, etc.) of various mammal and bird hosts, including humans. Thelazia nematodes are often referred to as "eyeworms."