In the United States this medication has a black box warning about fetal damage. For those who are elsewhere, a "black box warning" is the most serious warning

In the United States this medication has a black box warning about fetal damage. For those who are elsewhere, a "black box warning" is the most serious warning the United States Food and Drug Administration can require -- it's called that because they mandate that the manufacturer print the warning at the top of the package insert, surrounded by a black box to draw attention.