Do allergy eye drops make the pupil larger?

Should Not. They should not cause pupil dilation unless you are using a vasoconstricting agent (visine) when the drug wears off it can cause pupil dilation.
Maybe. Certain eye drops, even over-the-counter eyedrops can affect the pupil usually making it larger. There are many good allergy drops that do not cause mydriasis (dilation of the pupil). Consult your ophthalmologist for recommendations.