I'm not a doctor, but it could be caused by several things. Ring the hospital as soon as you can, only they will have the full information available on which to advise. Failing that, see your GP and get him or her to check and chase this up.
i am now just 2.5 years post Tomotherapy for throat cancer and in those early days I sounded like and 80 year old man, coughing up crap from my throat ... I was a fit and healthy 52 year old when I went through it
i used a nebuliser machine from the hospital ... it's a small portable thing so I had at home for about 3 months after treatment stopped and in the early days had to use it first thing in the morning and last thing at night
it helped, but time is really the healer and I am not sure how old your wife is, but I had targeted high does radiation and I was fairly fit and healthy, but it took ages to calm down
