Timberlake said he was faced with the decision to stop his tour early but ultimately decided to keep going.
Writing on Instagram, external on Thursday, he said: “As many of you know, I’m a pretty private person. But as I’m reflecting on the tour and festival tour – I want to tell you a little bit about what’s going on with me.
“Among other things, I’ve been battling some health issues, and was diagnosed with Lyme disease – which I don’t say so you feel bad for me – but to shed some light on what I’ve been up against behind the scenes.
“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.”
According to America’s Centers for Disease and Control and Prevention (CDC), patients treated with antibiotics in the early stages of the infection usually recover quickly and completely.
It adds most patients treated in later stages respond well to antibiotics, but some may have suffered long-term damage to the nervous system or joints.
Justin Bieber, Shania Twain and Avril Lavigne are among other singers to have struggled with Lyme disease.