My nephew has CF and is highly allergic to milk. He will be 15 this month. They said he would outgrow it, but it has never happened. And weight gain has been extremely difficult for him. He had a g-tube put in about 3 years ago, and it has helped some, but even then he is extremely thin. He was 2% body fat prior to that, and I don't know where he is now, but still not much more. Would hate to see how he would look without the g-tube. He also has to be given a special formula because of the milk allergy during night feedings in the tube.
There is a Parkay squeeze butter that he can have, that doesn't have milk. And he drinks rice dream milk, I think that is what it is called. Even antibiotics cause him problems, and he is given benadryl in his IV prior to the meds starting. I think that shop n save brand has a butter he can have as well.
My sister carries him butter with them when they travel, and they ask and request that there is no milk products to touch his food. He is highly allergic, and will get sick immediately after digesting it. Even his mouth touching it will affect him.
He truely is a challenge when it comes to CF appts and meeting with the diatricans. They are just running out of suggestions. I hope your son outgrows it, because it really has been a struggle to deal with on top of the CF needed weight gain. Good luck and just keep looking at labels and find something nice an fattening that he likes, and let him eat it whenever he pleases<img src="i/expressions/face-icon-small-smile.gif" border="0"> My nephew loves baked potatoes, eats many a day. He loves steak and chili and beef stew! Again, good luck!