Justin Bieber has revealed that he suffers from Lyme disease as well as a “serious case” of chronic infectious mononucleosis.

On Wednesday, the singer shared his medical condition on Instagram, and directly addressed derogatory comments about his appearance and health.

“While a lot of people kept saying justin Bieber looks like shit, on meth etc. they failed to realize I’ve been recently diagnosed with Lyme disease, not only that but had a serious case of chronic mono which affected my, skin, brain function, energy, and overall health,” he wrote.

He added that he was “getting the right treatment” after what he described as a “rough couple years”.

According to the Center for Disease Control, Lyme disease “is transmitted to humans through the bite of infected blacklegged ticks” and can usually be treated with antibiotics.

Typical symptoms include fever, headache, fatigue and skin rash. Left untreated, the disease can spread to joints, the heart and the nervous system.

Justin mentioned in the Instagram post that he will be discussing his health struggles in his upcoming YouTube Originals docuseries, Justin Bieber: Seasons.

Both the series and the announcement come on the heels of Yummy, his first solo single in four years.

Shortly after his announcement, Justin was defended by his wife Hailey Bieber, who hit out at those “trying to downplay the severity of Lyme disease”.

“Please do your research and listen to the stories of people who have suffered with it for years,” she urged. “Making fun of and belittling a disease you don’t understand is never the way, all it takes is educating yourself.”

She also praised singer Avril Lavigne, who has spoken out in the past about her own battle with condition, for “all you do to educate people about Lyme”.