The 33-year-old central midfielder, who has made nearly 300 league appearances in two spells at Ewood Park, sustained a knee injury in training on Monday and has undergone a minor operation.
The news comes just three days before Rovers meet their fierce rivals aiming to keep an unbeaten streak which stretches back 34 years.
Speaking to Blackburn's official website, boss Gary Bowyer said: "He aggravated the injury in training on Monday, we were fortunate to get him straight into hospital on Tuesday and his rehabilitation is now underway. We hope to welcome him back soon."
Bowyer will hope to include Jordan Rhodes in his squad despite the striker withdrawing from the Scotland squad at the start of the week due to a broken hand.