The U.S. Food and Drug Administration is urging parents not to feed children younger than 1 pacifiers with honey in them. 

The reminder comes after Texas Health Services said four infants were treated for botulism in the state.

The cases occurred between August and October. All of the children were given pacifiers containing honey that were purchased in Mexico. The infants are all unrelated and live across different parts of the state.

Texas DSHS defines botulism as a serious illness that is caused by a toxin attacking the body’s nerves. The illness can cause difficulty breathing, paralysis and can even result in death.

DSHS says to never give a baby under 12-months old honey. Bacteria in honey can produce the toxin in a baby’s intestine. Babies over one-year-old, develop new bacteria in their intestine that prevents botulism.

The DSHS issued an alert on botulism, advising health care professionals to educate parents on the illness and to remind everyone not to feed honey to babies under one-year-old. 

According to the DSHS, honey filled pacifiers are not that common in the US. However, they can appear in some specialty stores. The department also advises parents to avoid any pacifier containing other food substances since they too may pose a risk of causing botulism. 

There have been seven to eight reported cases of botulism a year in Texas in recent years. 2018 alone has seen ten confirmed or suspected cases.