Teenager shares video of ‘weird’ undiagnosed condition

A teenager is going viral after sharing a video of her self-described "weird, undiagnosed" condition.

TikTok user Madi Fischer shared the clip on May 12, where it's since received more than 550,000 views. In her video, the teen explains that whenever she works out, she only sweats on the right side of her body.

Fischer then shares a series of post-workout photos, in which her face is always only red and sweaty on one side.

"Weird, undiagnosed sickness check," she says at the start of the clip.

The video fascinated several TikTok users, who commented that they'd never seen anything like it before.

"THIS IS THE MOST INTERESTING THING IVE EVER SEEN PLS DO A VIDEO EXPLAINING," one user commented.

Some users wrote that they also faced similarly unusual sweating patterns, but hadn't realised others shared their experience.

"OMG I HAVE THIS!! I've never seen anyone else have it! Mines bad when exercising, my right cheek is always red," one commenter wrote.

Still, others were quick to help try and diagnose the teenager, pointing out that her symptoms mirrored those found in Harlequin syndrome.

That rare condition, which is thought to occur in women more often than men, is a syndrome that affects the autonomic nervous system, changing a person's sweating and skin flushing. In general, it's thought to be a benign condition that "is not known to affect a person's daily living or lifespan," according to the US Department of Health and Human Services.

Fischer wrote in her video's comments that while she had not been diagnosed with Harlequin syndrome, she has visited several doctors and her family now believes it's her most likely diagnosis.

"I've seen many doctors!!! it's just harlequins nothing life threatening," she assured her followers.

- This story first appeared on In The Know