They don't make such a thing as medicated layer feed. It is for chicks when they're most vulnerable to coccidiosis. By the time they're grown they are usually exposed enough to be resistant. The protozoa coccidia is the only thing medicated feed is for.
I don't feed medicated food to my chicks. I did have them vaccinated for coccidia. Now that they are grown and laying I feed them a good All Flock feed in pellet form as well as crushed oyster shells in a dish. I don't feed layer feed as I have roosters that don't need the added calcium that is found in layer feed.