It may have seemed like a good idea at the time. But at least three adolescents who accidentally breathed in instead of out on their homemade blowguns ended up in the emergency room after swallowing the pin (dart), according to a new study in the journal Pediatrics.

A simple search on the Internet was all the kids needed for step-by-step instructions on how to make a blowgun. At least 20 websites offer this information, but few warn readers what could happen if they accidentally swallow the dart.

The blowguns are made from a drinking straw. The dart is a pin or needle poked through the end of a shoelace. Blowing through the straw causes the dart to shoot out the other end.

The three adolescents in the study who swallowed the darts were coughing and had trouble breathing when they went in for medical help. It took two of them awhile before they admitted what had happened to the doctors and nurses. This led to longer suffering before the health care staff could find out what was bothering the patients. The injury is not very common.

Treatment usually includes anesthesia and using a long, medical instrument (bronchoscope) to remove the dart, according to the study. Sometimes, surgery is necessary if the doctor cannot reach the dart using the bronchoscope.

Other studies have reported on children who accidentally swallowed turban and scarf pins, which got stuck in the throat, lungs and elsewhere in the body. These patients needed the same kind of medical care.

Contact your pediatrician right away or go to the emergency room if your child is coughing or having trouble breathing and you suspect he or she has swallowed a pin, needle or other non-food item. Parents can encourage kids to talk about what happened, so they can be treated quickly.

They also can teach kids to think about possible dangers before trying an experiment they find online. Recent Internet risks kids have tried include swallowing dry cinnamon, stuffing as many marshmallows as possible in their mouths and purchasing alcohol.

© 2013 American Academy of Pediatrics. This Parent Plus may be freely copied and distributed with proper attribution.