What should I do when my 4-month-old stops breathing for a few seconds during a tantrum?
What you are describing is called a breath-holding spell. The name implies that children do this on purpose, but they do not. Breath-holding spells occur in 4 to 5 percent of children, can begin as early as 2 months, and rarely continue past age 5 or 6. They are probably a result of an overactive nerve that controls the diaphragm or a peculiarity of breathing that causes prolonged expiration in otherwise normal children.
Children can either turn blue or become pale, may pass out briefly, and even twitch a little before their breathing resumes. And it always does resume. The spells do not cause any harm except to parents' peace of mind. Although I constantly reassure parents about the benign nature of these spells, I have to admit I wait anxiously for breathing to begin when I watch one of these spells in the office.
Once the spell begins, there's little you can do to stop it. Sometimes blowing hard in the child's face or splashing a little cold water on her face can make her inhale and abort the attack. The biggest mistake is to live in fear of these episodes and give in to a child's demands in order to avoid them.