The child cries or gasps, forcibly exhales, stops breathing, and turns either blue (cyanotic form) or pale (pallid form).
An electrocardiogram (ECG, EKG) that records the electrical activity in the heart may be used to check for heart rhythm abnormalities, such as long QT syndrome, in children who have had a pallid breath holding spell.
If pallid breath holding spells are frequent and severe, a preventative anti-cholinergic medicine such as atropine sulfate may be prescribed, in consultation with a neurologist or cardiologist.
In a pallid BHS the brain sends a signal via the vagus nerve that severely slows the heart rate, leading to a temporary cessation of breathing and loss of consciousness.
Not getting enough rest: While fatigue generally does not make the circles appear on its own, it can make them easier to see, since your skin may look pallid.