According to a posting on the band's official website, Snow Patrol will have to reschedule two of their concerts, due to take place this week.
Lightbody said in the message: "The reason for this is my voice is in pieces. You may have seen us on 'Good Morning America' this morning and if you did you'll be aware I barely scraped through it and that was only one song."
"Unfortunately now I can barely hit any notes. My entire upper range has disappeared into a whisper," the singer said.
Lightbody said that he was due to see a specialist in New York tomorrow and may also seek help from a vocal coach in order to get his voice back to full strength.
"I am so sorry for this to all of you who have bought tickets especially those of you who have travelled long distances to these shows," he said.