is it common? do doctors know how to treat it?

I am going for my second test for Cystic Fibrosis soon, and I would like some information on Cystic Fibrosis in Adolescents. I am a 15 year old cancer survivor, and my doctors are testing me for CF to find a possible solution as to why I am not gaining weight. Please help. Thanks.

I have Cystic Fibrosis and I’ve been taking all of the enzymes and medications the doctors have given me and eating enough like the doctor said (as much as I can at a time) but I feel like I’m losing weight and I feel too thin compared to other girls my age. I’m still in my teens. Does anyone have any suggestions for me?

I have symptoms that sure sound like Cystic Fibrosis. Can it be possible for a 49 year old man to develop Cystic Fibrosis earlier in life and not realize it?

What kind of tests do doctors give for Cystic Fibrosis?