Justin Timberlake has revealed he has Lyme disease and opened up about the health challenges that have come with it.

In a post on Instagram Thursday, the pop singer, who wrapped up his two-year tour yesterday, called the tick-borne illness "relentlessly debilitating."

"If you've experienced this disease or know someone who has — then you're aware: living with this can be relentlessly debilitating, both mentally and physically," Timberlake, 44, wrote. "When I first got the diagnosis I was shocked for sure. But, at least I could understand why I would be onstage and in a massive amount of nerve pain or, just feeling crazy fatigue or sickness."

Early symptoms of a Lyme disease can include headache, fatigue, muscle aches, joint aches or stiffness, chills, fever and swollen lymph node

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