What Are Signs of a Salt-Wasting Crisis in Infants With CAH?

A salt-wasting crisis is a life-threatening medical emergency that requires immediate care. For infants with classic congenital adrenal hyperplasia (CAH), a crisis occurs when their bodies lose too much sodium (salt) and water while retaining too much potassium. The most critical early warning signs to watch for are vomiting, poor feeding, extreme sleepiness or lethargy, weight loss, and signs of severe dehydration ^[1][2]. If you notice these symptoms in your newborn, do not “wait and see” if they improve—seek emergency medical attention immediately.

Immediate Action Guidelines

When dealing with a potential adrenal crisis, seconds and minutes matter.

• Call Emergency Services (911) immediately if your baby: experiences physical collapse, abnormal breathing, unresponsiveness, seizures, or feels completely limp and floppy. Follow the dispatcher’s instructions. Do not attempt to drive a critically ill infant yourself. If your baby is unconscious or very drowsy, do not give feeds, fluids, or oral medicines by mouth due to the risk of choking.
• Go to the Emergency Department and follow your injection plan if your baby: has persistent vomiting, is unable to keep oral medications down, shows extreme lethargy, or has signs of severe dehydration. Give the emergency hydrocortisone injection exactly as your written plan directs, and proceed to the hospital. The injection is a critical first-aid measure, but it is not a substitute for an urgent hospital evaluation.

Key Warning Signs to Watch For

Parents should look out for the following warning signs:

• Vomiting: While many babies spit up small amounts, true vomiting in a baby with CAH is a critical warning sign ^[1][3]. Do not wait for vomiting to become “projectile” or “severe” ^[3]. Any vomiting that prevents your baby from keeping down feeds or their prescribed oral steroid medication requires immediate action ^[4].
• Poor Feeding: A sudden disinterest in eating, weakness while feeding, or an inability to keep milk or formula down can be an early indicator of a crisis ^[2][5].
• Extreme Sleepiness or Lethargy: Normal newborns sleep a lot, but if your baby is unusually difficult to wake up for feedings or lacks energy, take it seriously ^[2][5]. This lack of energy may present as hypotonia (a floppy or unusually limp baby) ^[6].
• Weight Loss: It is normal for newborns to lose a little weight immediately after birth, but continued weight loss or a failure to regain birth weight is a major warning sign ^[7][1].
• Signs of Severe Dehydration: Look for markedly fewer wet diapers, a dry mouth, cool or mottled (blotchy) skin, and a sunken fontanelle (the soft spot on the top of the baby’s head) ^[2]. Dehydration and a sunken soft spot can be late signs; you must act before waiting for them to appear if your baby is vomiting or lethargic.
• Physical Collapse or Pallor: Extreme paleness (pallor), abnormal breathing, or physical collapse are severe emergencies requiring an immediate ambulance ^[8][6].

When Does a Crisis Usually Happen?

While the risk of a crisis is particularly high during the first few weeks of a baby’s life, an emergency can happen at any time—especially during an illness ^[7][9]. Do not use the baby’s age as a reason to delay care if you see concerning symptoms ^[10].

A salt-wasting crisis causes dangerous but invisible changes in your baby’s blood—specifically low sodium (hyponatremia), high potassium (hyperkalemia), and sometimes low blood sugar (hypoglycemia) ^[1][2][5]. These imbalances can quickly lead to life-threatening heart rhythm problems or a dangerous drop in blood pressure (shock) ^[2][3].

Preparation and Your Emergency Plan

Always follow your endocrinologist’s written emergency plan. This plan will detail exactly when to give an emergency intramuscular (into the muscle) injection of hydrocortisone ^[4][11]. Never improvise a dose or give extra salt, water, or oral medicine unless explicitly instructed by your clinical team.

Preparation is key: keep your emergency injection kit in-date and accessible, ensure all caregivers are trained, and always carry an up-to-date emergency medical letter with the baby to hand directly to emergency medical responders or emergency department staff.