Researchers from the Centers for Disease Control looked at more than 1,000 laundry detergent exposures reported to poison centers.
They found children who ingested the pods were more likely to experience ill health effects such as vomiting, drowsiness and coughing.
That compares with children who ingested other types of laundry detergent such as powder or liquid.
The report says some young children who ingested the pods experienced breathing problems and seizures.
Since the pods look like candy, the study recommends keeping them well out of reach of children.