Medicated vs. Unmedicated Feed: How to Choose for Chicks and Game Birds

The first few weeks of a young bird’s life are the most vulnerable. Medicated starter feed is one of the simplest, most effective tools you have to protect them — but it’s not always the right choice. Here’s how to decide.

What Is Medicated Feed?

Medicated starter feed contains amprolium, a medication that helps prevent coccidiosis — a parasitic intestinal disease caused by coccidia protozoa that live in soil and can be fatal to young birds. Amprolium works by limiting the coccidia’s ability to absorb thiamine (vitamin B1), slowing their reproduction and giving young birds’ immune systems time to build natural resistance.

It’s not an antibiotic. It doesn’t treat an active infection. It’s a preventive tool, and it works best when used from day one.

Why Coccidiosis Is Such a Risk

Coccidia are everywhere — in soil, bedding, and on the ground your birds will eventually explore. Young birds have no natural immunity and can go from healthy to critically ill within 24–48 hours of a heavy exposure. Symptoms include bloody or watery droppings, lethargy, hunched posture, and loss of appetite. By the time you notice signs, the disease is already advanced.

Prevention is far easier than treatment. Medicated feed gives your birds a fighting chance while their immune systems develop.

Medicated vs. Unmedicated: How to Choose

The decision comes down to one question: were your birds vaccinated for coccidiosis at the hatchery?

• Not vaccinated: Use medicated starter. The amprolium provides protection while their immunity develops naturally through gradual low-level exposure.
• Vaccinated for coccidiosis: Use unmedicated starter. Amprolium can interfere with the vaccine’s effectiveness by limiting the low-level coccidia exposure the vaccine relies on to build immunity.

If you’re not sure whether your birds were vaccinated, check with your hatchery or feed store. When in doubt, medicated is the safer default for unvaccinated birds.

Our Medicated Feed Options

For Chicks

Heim Milling – 20% Chick Starter-Grower Crumble (Medicated)

Our go-to medicated starter for backyard chicken keepers. At 20% protein in a fine crumble form, it’s perfectly sized for day-old chicks and supports strong, steady growth through the brooder stage and beyond. Locally milled in Minnesota.

Shop it: Heim Milling 20% Chick Starter-Grower Crumble (Medicated)

For Game Birds

Heim Milling – 30% Game Bird Starter Crumble (Medicated)

Designed for the high protein demands of game bird chicks — turkeys, pheasants, quail, and similar species — during their earliest weeks. The elevated protein supports rapid early development while amprolium provides coccidiosis protection.

Shop it: Heim Milling 30% Game Bird Starter Crumble (Medicated)

Heim Milling – 24% Game Bird Chick Grower Crumble (Medicated)

For game birds transitioning out of the starter stage, this grower formula maintains elevated protein for continued development while keeping coccidiosis protection in place through the higher-risk juvenile period.

Shop it: Heim Milling 24% Game Bird Chick Grower Crumble (Medicated)

Our Non-Medicated Feed Options

Prefer to skip amprolium? Whether your birds were vaccinated, you’re raising organically, or you simply prefer a clean-ingredient approach, we carry non-medicated options across both chick and game bird lines.

For Chicks

Heim Milling – 20% Chick Starter-Grower Crumble (Non-Medicated)

The same locally milled, high-quality 20% protein crumble — without amprolium. The right choice for vaccinated chicks or keepers who prefer unmedicated feed.

Shop it: Heim Milling 20% Chick Starter-Grower Crumble (Non-Medicated)

Luxemburg’s Feed Service – 22% Non-GMO, No Corn No Soy Chick/Poultry Starter Mash

For keepers who prioritize clean ingredients, Luxemburg’s Non-GMO, corn-free, soy-free starter mash is an excellent unmedicated option. Locally milled in Minnesota with a focus on simple, quality ingredients.

Shop it: Luxemburg’s 22% Non-GMO No Corn No Soy Chick Starter Mash

For Game Birds

Heim Milling – 24% Game Bird Chick Grower Crumble (Non-Medicated)

The non-medicated version of our game bird grower — ideal for vaccinated birds or those that have moved past the highest-risk coccidiosis window.

Shop it: Heim Milling 24% Game Bird Chick Grower Crumble (Non-Medicated)

Luxemburg’s Feed Service – 19% Non-GMO, No Corn No Soy Grower Mash

A clean-ingredient grower option for game birds and poultry raised without corn or soy. Non-GMO and locally milled — a great fit for keepers who want to know exactly what’s in their feed.

Shop it: Luxemburg’s 19% Non-GMO No Corn No Soy Grower Mash

When to Use — and When to Stop

• Start on day one: Begin medicated feed as soon as birds arrive. Don’t wait for signs of illness.
• Continue through weeks 6–8 for chicks, 6+ weeks for game birds: Most birds can transition to a non-medicated grower feed once they’ve had time to build natural coccidia immunity through gradual exposure.
• High-risk environments: If coccidiosis has been a problem before, or brooder conditions are difficult to keep clean and dry, consider extending medicated feed use or consulting your vet.
• Don’t use with vaccinated birds: Amprolium can undermine coccidiosis vaccination.

A Note on Egg Withdrawal

Amprolium has no established withdrawal period for eggs in the US — meaning eggs from hens fed amprolium-containing feed are generally considered safe to eat. That said, medicated starter is designed for young birds, not laying hens. Switch to layer feed once your pullets begin laying.

Have questions about which feed is right for your flock? Stop in or browse our full feed collection at BloomingtonFarmAndFeed.com — we’re happy to help you find the right fit.