Swallowing a penny used to be no big deal when they were copper. Now that they're mostly zinc, they're bad news if they don't pass quickly.
the chemical reaction between zinc and stomach acid (hydrochloric acid) is similar to that in wet cell batteries and would likely be caustic to the stomach lining. Apparently, when the penny became trapped in the boy's stomach, its zinc base reacted with stomach acid to produce hydrogen gas and zinc chloride (a major ingredient in the smoke from smoke bombs). According to O'Hara, this chemical reaction dissolved the zinc base of the coin, creating holes in the coin and ulcerations in the stomach lining. [...] While one penny is not typically enough to cause such systemic damage in a child, it can spell trouble for a pet. [...] Children and pets who swallow pennies should be monitored to ensure the coin passes. If it doesn't show up within two days or if the swallower starts having stomach problems, the child or animal should be taken to the doctor immediately.
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Yeah, Roger, the problem with the penny (according to my Vet Tech wife) is not the size, but the Zinc. She has seen several dogs die from Zinc toxicity, and others that have required surgery to remove a penny. Make sure you go and make sure your vet takes it seriously (mention Zinc toxicity if you must). Good luck!
posted by Rock Steady at 2:41 PM on January 26, 2006
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I think I'd talk to the vet and go through the "what ifs" with them in case it was a pennny. Then you'll know what you should be watching for.