Welcome to HCM,
I can understand your concern about your daughter,if I am right she is taking ?Atenolol
which is drug for blood pressure and also may be useful in migraine
.Please check once more what drug she is taking.
Visual disturbances are reported but are not common side effect of this drug,
If she is having visual disturbance and any irritation in eyes this could be due to possibly this drug so please visit your Physician and he/she can taper the dose and if required some other alternative may be used may be from other group.
Please take care of her