Chewed or swallowed batteries cause chemical burns and heavy-metal poisoning.
Lithium button batteries are particularly dangerous because they can burn through tissue within hours.
Disc/button batteries generate a chemical burn when wedged against mucous membranes — current passes through tissue and can perforate the esophagus or gut in 2–4 hours. Alkaline batteries leak corrosive potassium hydroxide. Zinc and lead exposure from chewed batteries can also cause heavy-metal toxicity.
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Any swallowed battery is an emergency, especially a button battery. Do not induce vomiting — re-exposure to caustic contents worsens injury.
Contact your veterinarian or an emergency animal poison hotline immediately. Do not induce vomiting unless instructed by a vet.
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