If your child swallowed a penny and is breathing normally, not choking, and not in obvious distress, the coin will most likely pass through their digestive system on its own. Pennies are the most commonly swallowed coin among children. Still, you should call your pediatrician promptly because an X-ray is typically needed to confirm where the penny is and rule out a more dangerous object like a button battery.
Signs That Need Immediate Attention
Most children who swallow a penny show no symptoms at all, especially once the coin reaches the stomach. But some kids will have warning signs that the penny is stuck, usually in the esophagus (the tube connecting the throat to the stomach). A U.S. penny is 19 mm across, and a child’s esophagus has three natural narrow points where it can get lodged: near the throat, at the middle of the chest where major blood vessels cross, and just above the entrance to the stomach.
Watch for these symptoms, which suggest the penny hasn’t made it to the stomach:
- Drooling or pooling saliva that your child can’t seem to swallow
- Gagging or choking
- Vomiting
- Refusing to eat or drink
- Pointing to or complaining about chest or throat pain
- A sensation of something being “stuck”
If your child is having any trouble breathing, call 911 immediately. If they’re showing any of the other symptoms above but can breathe fine, head to the emergency room rather than waiting for a pediatrician appointment.
Why Your Child Needs an X-Ray
Even if your child seems completely fine, doctors recommend an X-ray whenever a coin ingestion is observed or suspected. The X-ray does two important things. First, it shows whether the penny is in the esophagus (where it may need to be removed) or in the stomach or intestines (where it will likely pass naturally). Second, and just as critically, it helps distinguish a coin from a button battery, which looks similar but is a medical emergency. Button batteries on X-ray show a characteristic “double halo” outline that coins don’t have.
Your pediatrician can guide you on whether to come into the office or go to the ER. In most cases, if your child is showing no symptoms and the X-ray confirms the penny is already in the stomach, you’ll be sent home to monitor and wait.
What Happens When the Penny Reaches the Stomach
Once a penny makes it past the esophagus and into the stomach, the odds are strongly in your favor. For children with no symptoms, doctors typically observe for about 24 hours to see if the coin moves along on its own. If the child develops symptoms like vomiting or abdominal pain during that window, doctors will remove the coin within 24 hours using an endoscope (a thin, flexible tube passed through the mouth).
If the coin moves into the small intestine and your child remains comfortable, the approach is simply to wait for it to pass in the stool. Your doctor may order follow-up X-rays every one to two weeks until the penny is confirmed gone.
Monitoring Your Child’s Stool
Once you’re home, you’ll need to check your child’s stool for the penny. This is exactly as unpleasant as it sounds, but it’s the only reliable way to confirm the coin has passed. The simplest method is to have your child use a potty or a container you can inspect, or to place a disposable strainer or old colander in the toilet. You’re looking for a small, round metallic disc. It may be discolored but will be unmistakable.
Most small foreign objects pass within a few days, though it can take longer. If the penny doesn’t appear in the stool, your doctor will likely order X-rays every 48 to 72 hours initially, then weekly, to track its progress. A penny that stays put for more than one to two weeks in the stomach is a concern and may need to be removed.
The Zinc Risk in Modern Pennies
Here’s something most parents don’t realize: pennies minted after 1982 are made almost entirely of zinc with just a thin copper coating. That matters because stomach acid can corrode zinc quickly. In lab studies simulating stomach conditions, post-1982 pennies showed visible erosion within 24 hours. By day two, full-thickness holes had developed through the coin’s surface. Over seven days, these pennies lost 5% to 8% of their weight, meaning that zinc was dissolving directly into the simulated stomach fluid.
If the copper coating is already scratched or damaged before your child swallows it, the chemical reaction with stomach acid begins immediately, producing gas bubbles on contact. Even undamaged pennies start showing a reaction by the third day.
This is why a penny that lingers in the stomach is more concerning than other coins. Quarters, nickels, and dimes showed no corrosion over the same seven-day period in testing, and pre-1982 copper pennies were similarly stable. If follow-up X-rays show a penny with scalloped edges or holes, that’s a sign it’s been sitting in stomach acid too long and should be removed by endoscopy. Prolonged zinc exposure can cause ulceration of the stomach lining and, in rare cases, zinc toxicity.
Warning Signs in the Days After
While you’re waiting for the penny to pass, keep an eye out for symptoms that suggest a complication like a bowel obstruction or perforation. These are uncommon with a smooth, small object like a penny, but they require immediate medical care:
- Worsening abdominal pain
- Vomiting, especially if it contains blood
- Bloody or dark, tarry stool
- Fever
- Unexplained weight loss (more relevant if the object is retained for weeks)
Any of these symptoms after a known coin ingestion warrant a trip to the emergency room. A foreign body retained in the stomach or intestines for an extended period can cause irritation, ulceration, or in rare cases a small perforation that leads to infection.
What Not to Do
Don’t try to make your child vomit. A coin coming back up can get stuck in the esophagus or, worse, be inhaled into the airway. Don’t give your child large amounts of bread or water in hopes of pushing the coin along; this hasn’t been shown to help and can make imaging harder to interpret. And don’t assume that because your child seems fine, the situation doesn’t need medical evaluation. The X-ray to confirm location and rule out a button battery is a simple, quick step that matters.