What symptom of hypoglycemia beta blockers don't mask ?

Neuroglycopenic: Beta blockers block the adrenergic symptoms of hypoglycemia, such as shakiness, palpitations, sweats, but will not block the neuroglycopenic symptoms that are related to inadequate glucose supply to the brain, such as confusion, seizures, visual changes, and passing out. However, these symptoms are only likely to occur in diabetics on meds that can cause excessive amounts of insulin.