Scottish doctors report treating five children for injuries after swallowing liquid detergent capsules during the last year and a half.

The kids, all younger than 2, showed up in the emergency room with similar symptoms: drooling and stridor (breathing marked by a whistling sound caused by a narrowed airway). Most were treated with steroids and the placement of tubes to help the kids breath.

The Scottish doctors say there's a been a rise in reports of poisonings like these in the U.K. Calls from health professionals about detergent capsules to the national poisoning hotline there hit 647 last year. The capsules have become the most common household products to be swallowed by kids.

"We feel that the increasing trend in liquid detergent capsule ingestion poses a significant public health issue," they wrote in a letter published online by the Archives of Disease in Childhood.

The doctors theorize that caustic ingredients in the detergent capsules are causing damage. "The chemicals within are highly irritative and cause quite marked ulceration and damage to the tissues of the upper aerodigestive tract," Dr. Lyndsay Fraser, the lead author of the recent letter, tells Shots by email.

Here in the U.S. the detergent pods continue to cause problems. In August, there were 735 calls to poison control centers about children under 5 being exposed (swallowing, inhaling, getting the stuff in their eyes, etc.) to laundry packs, according to the latest figures form the American Association of Poison Control Centers. That's up from 725 calls in July and 639 in June. So far this year, there have been 2,950 calls altogether. No deaths have been reported.

Dr. Michael Beuhler, medical director for the Carolinas Poison Center, tells Shots, that a look at the capsule ingredients hasn't found a "smoking gun" for the health problems that have been reported. "Nothing is sticking out," he says.

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