Justin Bieber on Friday announced that he is taking a break from performing after being diagnosed with Ramsay Hunt syndrome (RHS), a rare condition that has paralyzed one side of his face. 

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Justin Bieber's symptoms

According to Bieber, he is experiencing paralysis on one side of his face, which has left him unable to perform.

"It is from this virus that attacks the nerve in my ear and my facial nerves, and has caused my face to have paralysis," Bieber said in a video posted on Instagram. "As you can see, this eye is not blinking," he continued. "I can't smile with this side of my face, this nostril will not move, so there is full paralysis in this side of my face."

Bieber then addressed his fans who were "frustrated" about his postponed performances. "I'm just physically, obviously not capable of doing them," he explained. "This is pretty serious as you can see. I wish this wasn't the case but obviously, my body is telling me I got to slow down and I hope you guys understand and I'll be using this time to rest and relax and get back to 100% so that I can do what I was born to do."

"But in the meantime," he added. "This isn't it. I got to get my rest on so that I can get my face back to where it's supposed to be."

"I'm gonna to get better and I'm doing all these facial exercises to get my face back to normal and it will go back to normal, it's just time," he said.

What is Ramsay Hunt syndrome?

According to the Mayo Clinic, RHS "occurs when a shingles outbreak affects the facial nerve near one of your ears. In addition to the painful shingles rash, Ramsay Hunt syndrome can cause facial paralysis and hearing loss in the affected ear."

RHS, which was initially described in 1907 by James Ramsay Hunt, is triggered by an infection of the varicella-zoster virus (VZV), the virus that causes chickenpox and shingles, meaning individuals diagnosed with either of those conditions are also at risk of developing RHS.

Still, RHS is relatively rare. Each year, an estimated five out of every 100,000 people in the United States will develop RHS, according to the National Organization for Rare Disorders,

RHS can cause a painful rash on the outer area of the ear and ear canal and severe ear pain, as well as a spinning sensation, according to Mount Sinai Health System. Most cases also result in some degree of facial paralysis.

However, these symptoms do not manifest in every case. In some instances, an individual will only experience facial paralysis, which requires a blood test to confirm the presence of VZV. In others, visible inflammation may spread down to an individual's soft palate and throat.

Other notable symptoms include tinnitus, ear pain, and some hearing loss. In rare cases, an individual may also experience amplified hearing, vertigo, nausea, loss of taste, dry mouth, or dry eyes.

If the condition is not treated within three days of symptom onset, it can result in deafness and permanent weakness in the facial muscles, according to the Mayo Clinic. Treatments include antiviral medications such as acyclovir or famciclovir, alongside anti-inflammatory corticosteroids, such as prednisone, the New York Post reports.

While about 75% of those who develop RHS will recover completely, 25% develop some type of long-term nerve damage.

During treatment, Mouth Sinai recommends patients wear an eye patch to prevent any injury to the eye. (France, CNN, 6/10; Wenger, People, 6/10; Bisset, Washington Post, 6/11; Garner, People, 6/10; Scribner, Axios, 6/10; Sparks, New York Post, 6/10)