Disclosed is an isolated monoclonal antibody that specifically binds to at least one of a canine IL-31 or a feline IL-31, wherein said antibody or antigen-binding portion thereof reduces, inhibits, or neutralises a pruritic condition or an allergic condition in a dog or cat. Also disclosed is a method of treating a condition or disorder selected from a pruritic condition or an allergic condition, comprising administering a therapeutically effective amount of the above-described antibody to a non-human animal.
