If your child swallows a magnet or battery, take him to the ER. It's especially dire if he swallows more than one because they could adhere to each other in the body, causing serious internal harm.

Here, how to treat three of the more common (and usually less dangerous) scenarios related to foreign objects. While less alarming, in all instances, seek prompt medical attention.

Swallowing a penny

Most coins, marbles, and buttons will pass safely out of the body in a bowel movement within 7 to 10 days. But you should still alert your doctor about any ingested foreign object; she may recommend an x-ray to make sure it isn't wedged in the stomach lining. Call right away if your child is alert but starts to cough or drool, or if he can't eat or drink -- the penny may be stuck in his esophagus and need to be removed surgically or with an endoscope.

If your child is choking on the object, follow our instructions for choking.

A crayon in the ear

A crayon will most likely get stuck in the ear canal and muffle her hearing; small objects rarely puncture the eardrum and cause permanent hearing loss. But the ear canal can get infected, so have your doctor remove the crayon. (Do not dig it out on your own as you may not get the whole thing or it could break off and move deeper inside).

A bead up the nose

A bead can damage internal nasal structures and possibly cause an infection, especially if it keeps mucus from draining. (Bad breath is often a symptom.). Your pediatrician should be able to remove it; if the object can be seen, a child may be able to blow it out with the help of a doctor. Don't try to dig it out with your finger; you may accidentally push it farther in.