When Dr. Yasir Hamad heard that a patient's tongue had turned black, he decided he needed to see it for himself.
在亚西尔·哈马德医生听说一位病人的舌头变黑了的时候，他决定自己要去一看究竟。
"It was the typical textbook case of a condition known as black hairy tongue," said Hamad, an assistant professor in the Department of Medicine at the Washington University School of Medicine in St. Louis.
圣路易斯华盛顿大学医学院医学系助理教授哈马德表示：“这是科书般的典型案例。”
Despite the name, black hairy tongue isn't hair at all. It refers to tiny nubbins on the tongue, called papillae, that have grown longer and turned black.
尽管有这么个名字，但舌头上的黑毛根本就不是头发。它其实是舌头上的小疙瘩，称为乳头状突起，当它长得更长时，就会变黑。
These bumps, normally less than a millimeter long, can reach between 12 and 18 millimeters, according to a review last year.
去年的一份报告显示，这些突起正常情况下不到一毫米长，但变成肿块时可以达到12到18毫米。
As the papillae grow, they are thought to trap microscopic food particles, giving bacteria and other microbes a chance to thrive on the tongue -- causing a strange discoloration.
随着乳突的生长，它们可以捕获微小的食物颗粒，这就给了细菌和其他微生物在舌头上生长的机会，最终导致奇怪的变色。
Black hairy tongue is an uncommon and harmless side effect of some drugs, but it can also be linked to smoking, poor oral hygiene and certain medical conditions.
黑毛舌也是一些药物的副作用，少见却无害，但也可能与吸烟、口腔卫生不良和某些疾病有关。

Hamad's patient, a 55-year-old woman, had received an antibiotic called minocycline to deal with an wound infection after a motor vehicle accident, according to his report. Within a week, her tongue turned black, she began to feel nauseated, and there was a foul taste in her mouth.

哈马德的病人是一名55岁的妇女，他的报告显示，她在一次机动车事故后接受了一种名为二甲胺四环素的抗生素治疗伤口感染。之后不到一个星期，舌头就变黑了，她开始感到恶心，而且嘴里有股难闻的味道。
"As scary as this looks, the good part is that it's actually reversible," Hamad said. Four weeks after doctors changed her medication regimen, the patient's tongue returned to its normal color.
哈马德表示：“虽然看起来很可怕，但好在它其实是可逆的。”在医生改变她的治疗方案四周后，病人的舌头恢复了正常的颜色。
It's unclear exactly how uncommon this is, Hamad said, but it's the first case he's seen in 10 years of practicing.
哈马德称，目前还不清楚这种情况有多罕见，但这是他10年来第一次遇到这种情况。
If your tongue starts to look suspiciously black and hairy, he added, don't panic, and "check with your primary doctor, because some other conditions can resemble this."
他补充说，如果你的舌头开始变得黑乎乎、毛茸茸的，不要惊慌，“去找你的主治医生看看，因为有些其他的病症可能会跟这个相似。”