child hair loss

My son is 14, since he was 11 he has had reacurring hair loss, It always starts in the same place "the crown" works out in a circular motion, and grows back. i'm concrned now that this is still happening, especially as he is reaching his 15. i have noticed that when he is starting to lose the hair his scalp is reddish, I have taken him to the gp who dismisses it every time stating the it is just alopicia, but sureley it has to be something else. the patch gets quite big, and i'm really concerend as he is doing his big exams this next two years and dont want it to effect him anymore than it already has.

Any info greatly appreciated.

[Fuzzz]

Recently they have started linking gluten intolerance/celiac disease with alopecia.  Get him tested for celiac disease.  After you have the results, even if they are negative, he might still have an allergy.  Stopping gluten might solve his problem.  It's not an easy diet, but it's healthy.