My son has cf and has been taking ivacaftor since January 2013 his behaviour has changed for the worse in this time he,s very angry one minute then bouncing off the walls the next, he,s very argumentive never does as he is told I know most children have times when they don't listen and do as they are told but my son never listens he has other problems like hydrocephalus with a shunt, also global development delay he,s been tested for ADHD and autism both came back negative. This real bad behaviour has increased 100% since February/march 2013 do you know if it could be related to ivacaftor?