Why Is My Chicken's Eye Swollen, Foamy, or Stuck Shut?
Foamy, bubbling, or swollen-shut eyes in chickens are usually respiratory disease surfacing at the eye — treat it as a sinus/airway issue, not just an eye issue.
Most likely causes
Mycoplasma (MG) and friends
What points to it: Bubbles or foam in the eye corner, swollen sinus below the eye, sneezing, spread between birds.
What to do: Isolate, warmth, and vet-guided antibiotics (MG responds to specific families) — plus the flock-carrier conversation: MG stays in a flock, which affects selling/hatching decisions.
Coryza
What points to it: Dramatic facial/eye swelling with a distinctly foul smell around the head.
What to do: Vet promptly — coryza is bacterial, treatable, and stinks (literally) if delayed.
Injury or peck
What points to it: One eye, sudden, with a visible scratch or wound; no sneezing, no spread.
What to do: Rinse with sterile saline, apply plain terramycin eye ointment (feed-store staple), isolate from peckers, and monitor.
Ammonia burn
What points to it: Both eyes irritated across multiple birds in a tight-shut winter coop that stings YOUR eyes at bird height.
What to do: Ventilation fix immediately; eyes recover once the air does.
Check these first
One eye vs both, foam vs clear tearing, smell test near the head, coop air check at night, and a flock scan for sneezers — the combination sorts injury from infection from environment in minutes.
When it's probably nothing
A brief watery eye after a dust bath that clears within hours, or one dramatic eyelid stretch mid-preen, needs no treatment.
This guide is experienced-keeper guidance, not veterinary care. When a bird is crashing or a symptom is spreading, a poultry vet or your state extension lab is the right call — fast.
📄 Free printable: The Chicken Never List
The 15 foods that can hurt your flock, on one page — print it, tape it inside the feed-bin lid.
Harold knows your flock's history
Homestead Paradise keeps your flock's health records, lay records, and feed history — so when something looks off, Harold answers with your birds' actual story, not generic internet advice. Snap a photo with Harold's Eyes and log what you find, so next time you'll know what worked.
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