17 children in Spain developed a condition known as 'werewolf syndrome' after they were accidentally given hair loss drugs

• 17 children in Spain contracted "werewolf syndrome" after a drug manufacturer mistakenly filled heartburn remedy with hair loss treatment.
• The condition, known formally as hypertrichosis, causes thick hair to grow all over the body.
• The children developed the condition after minoxidil, a drug to halt hair loss, was given out by doctors who thought it was omeprazole, a common heartburn remedy, by Farma-Química Sur SL.
• The bottles have now been removed from pharmacies across Spain.
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At least 17 children in Spain have developed "werewolf syndrome," a condition that causes thick hair to grow all over the body, after they were accidentally given hair loss medication by doctors.

Between April and June, the children, living across Spain, were given what doctors thought was omeprazole, a remedy for heartburn. The bottles were, however, filled with of minoxidil, a drug to stem hair loss and treat conditions such as alopecia and male pattern baldness, El Pais reported.

As a result, thick hair grew all over the children's bodies, a condition called hypertrichosis, known popularly as "werewolf syndrome." 

This video from Spain's El Mundo newspaper shows images of some of the 17 children affected. 

Parents of some of the children affected by the mix up told El Pais that seeing their babies sprout unexpected hair was "very scary," as they did not know what was happening.

"My son's forehead, cheeks, arms and legs, hands became covered in hair … He had the eyebrows of an adult. It was very scary because we didn't know what was happening to him," said Ángela Selles, a mother from Granada in the Andalusia region of Spain told the newspaper.

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Another mother in Granada, who was not named, told El Pais that she took her three-month-old son to numerous doctors in an attempt to find out what was wrong with him.

"We went to the pediatrician and they told us it could be something genetic or to do with his metabolism. We had to start going to specialists to rule out several syndromes and rare conditions," she told El Pais.

In total, 10 of the children affected were from the northern province of Cantabria, four were from Andalusia in the south, and three were from the eastern coastal region of Valencia.

The company who supplied the drug to pharmacies in Spain was Farma-Química Sur SL, which imported the minoxidil from Smilax Laboratories Limited, based in India.

The Spanish Agency of Medicines and Medical Devices said the mistake had occurred when a shipment of minoxidil sent by Smilax Laboratories Limited to Farma-Química Sur SL was mixed up with one of omeprazole, Granada Hoy reported.

Farma-Química Sur SL then "put this medication in a container that was marked omeprazole" Spain's health minister, Maria Luisa Carcedo, said on Wednesday.

The medication in question has been removed from pharmacies across Spain, and a laboratory belonging to Farma-Química Sur SL had been temporarily closed.

The case in Spain is not the first incident involving hypertrichosis to come to light in 2019.

Earlier in the year, the case of an Indian schoolboy named Lalit Patidar was widely reported by global media. 13-year-old Patidar has a severe genetic case of hypertrichosis, leading his face to be entirely covered by thick blonde and brown hair.

"I was born with too much hair on my face and this makes me different," he said, according to a report from the the Daily Mirror.