(CNN) - Justin Bieber says he’s battling Lyme disease.
The singer made the announcement on Instagram Wednesday, saying he was diagnosed only recently.
He wrote he also had a serious case of chronic mono, which affected his skin, brain function and overall health.
Bieber said he'll reveal more details in his upcoming YouTube documentary, but for now, he said he's getting the right treatment and will be back better than ever.
Last week, Bieber released his first solo single in four years, titled "Yummy."
Lyme disease is usually carried by ticks. The Centers for Disease Control and Prevention says if the disease is not treated, it can affect the joints, heart and nervous system.