If your child swallows a small object such as a coin, it may be tempting to wait for it to come out the other end. But if that object is a miniature disk or “button” battery, it could be a medical emergency.

Each year, nearly 2,000 people swallow button batteries, which are used in hearing aids, toys, watches, calculators, greeting cards, remote control devices and other products, according to the National Capital Poison Center. Sixty-two percent of battery ingestions involve children under the age of 5 years, with a peak incidence in 1- and 2-year-olds. However, many cases involve adults and older children, who hold a battery in their mouth while working and inadvertently swallow it if they are startled.

While most button cells pass through the body and are eliminated in the stool, some may lodge in the esophagus. A battery that gets hung up may stick to tissue and leak, causing a chemical burn. Larger batteries (20 to 23 millimeters in diameter) are more likely to get lodged.

If your child swallows a battery, act immediately:

Do not give ipecac.

Obtain an X-ray immediately to be sure the battery has gone through the esophagus into the stomach. A battery lodged in the esophagus can cause severe burns in just two hours. Battery removal is done with an endoscope; surgery is rarely, if ever, necessary.

If a battery has moved beyond the esophagus, the patient can be sent home to wait for the battery to pass. Passage may take many days or even months. Report fever, abdominal pain, vomiting or blood in the stools immediately to your physician and to the National Button Battery Ingestion Hotline at 202-625-3333.

Button batteries also may cause severe injury when placed in the nose or ear. Immediate removal is essential. Never use nose or ear drops until the person has been examined by a physician as these fluids cause additional injury if a battery is involved.

For more information about button battery injuries, visit www.poison.org/prevent/battery.asp.

©2008 American Academy of Pediatrics. This information may be freely copied and distributed with proper attribution.