The present invention relates to arthropod epoxide hydrolase proteins; to arthropod epoxide hydrolase nucleic acid molecules, including those that encode such epoxide hydrolase proteins; to antibodies raised against such epoxide hydrolase proteins; and to other compounds that inhibit arthropod epoxide hydrolase activity. The present invention also includes methods to obtain such proteins, nucleic acid molecules, antibodies, and inhibitory compounds. Also included in the present invention are therapeutic compositions comprising such proteins, nucleic acid molecules, antibodies and/or inhibitory compounds as well as the use of such therapeutic compositions to protect animals from hematophagous arthropod infestation.