January 13, 2006
Other
Question from Hamilton, Ontario, Canada:
The pupils of my son’s eyes can be unusually large compared to the pupils of people standing beside him in the same brightly lit room, in the same position as he is. His pupils are uniformly large (same size — one not bigger) and dilate slightly when he is taken to different rooms/different light strengths. His non-diabetic sibling’s pupils will change size dramatically given the same circumstances. I have asked our Diabetes Clinic team and they do not have an answer except to monitor. I have been unable to “link” it to specifics, but first noticed it after a Humalog injection at dinnertime. He is also taking Humulin NPH in the morning and evening. He is on Singular, 5 mg, at bedtime and Symbicort 200, in the morning and at bedtime for asthma. He was diagnosed with type 1 in April 2004 at the age of nine, but recalls symptoms from the year previous (shaky before lunch at school). I did not find a similar question on your web site.
Answer:
I would not worry about the large pupil size. There is great variation in the normal population, even amongst family members. None of your son’s medications are pharmacologically capable of dilating the pupils; in fact, Symbicort is capable of constricting the pupils. His pupils dilate less than his sibling’s because they are already large to begin with. Over time, most patients with diabetes develop smaller than average pupil size as a result of autonomic neuropathy, but your son is too young and hasn’t had diabetes long enough to have this happen, thankfully. I would suggest that you have him wear sunglasses or UV blocking lenses when he is outdoors to keep harmful ultraviolet rays from reaching the internal eye (all of us should be doing this!)
PC
