Can I use eye makeup if I have pterygium?

Yes. Prevention is key remedy. Avoid sun (sunglasses, hat); avoid smoking. Natural rx info: see eyedoc2020.blogspot. Com; Other ways to help decrease symptoms: cold artificial tears, nsaid drops, low dose or hi dose steroids (though risk of glaucoma, cataract); surgery is only real way to remove/cure: though 5-15% risk of recurrence. Best of luck.
Yes. A pterygium is on the surface of the cornea and shouldn't be affected by properly applied eye makeup.