On Thursday, the singer shared a lengthy message via Instagram about his Lyme disease diagnosis, which he called "relentlessly debilitating."

Chris Kirkpatrick is in awe that his former ‘NSync bandmate Justin Timberlake performed a full tour amid a battle with Lyme disease. "I've always known my little bro was tough - but this tour showed me a whole new level of strength,

LOS ANGELES — Justin Timberlake has been diagnosed with Lyme disease, the former NSYNC star said on Instagram Thursday. Timberlake shared the news in a post commemorating his Forget Tomorrow tour, which wrapped in Turkey on Wednesday, adding that the disease “can be relentlessly debilitating, both mentally and physically.”