What Should I Do if My Child Vomits a CAH Stress Dose?

If your child has Congenital Adrenal Hyperplasia (CAH) and begins vomiting and cannot keep their oral hydrocortisone down, you must act immediately. Vomiting makes medication absorption unreliable, which can allow a life-threatening adrenal crisis to develop rapidly ^[1][2].

Emergency Action Plan

When your child is vomiting, follow your endocrinologist’s written sick-day plan. In general, if they vomit an oral stress dose, the plan may advise trying to repeat the dose once. However, if they cannot retain the oral medication or vomiting continues:

1. Give the emergency injection: Administer the intramuscular (IM) hydrocortisone injection immediately ^[1]. Use the exact pre-calculated dose listed in your child’s emergency letter.
2. Seek emergency care: Go to the nearest emergency department or call emergency services (911) ^[3]. The emergency injection is a bridge to keep your child safe, not a complete treatment.
3. If you have no kit or it is expired: Call emergency services immediately. State that your child has CAH, is in danger of an adrenal crisis, and needs emergency medical help. Do not wait for a prescription refill.

When to Call an Ambulance Immediately

Call emergency services right away—and do not attempt to drive your child yourself—if your child shows any of these “red flag” signs of a severe crisis ^[2][4]:

• Unusual sleepiness or inability to wake up
• Confusion or fainting
• Seizures (convulsions)
• Severe weakness, pallor, or cold, clammy skin
• Inability to safely swallow
• Note: Never give anything by mouth to a child who is unconscious, having a seizure, or unable to swallow safely.

Why Vomiting is a Medical Emergency in CAH

When a child is sick, their body requires extra cortisol to handle the physical stress ^[5]. When vomiting prevents the body from absorbing this hormone, it loses the ability to regulate blood pressure, blood sugar, and fluid balance ^[2][6].

For children with the “salt-wasting” form of CAH, losing fluids through vomiting or diarrhea is particularly dangerous because they also lack mineralocorticoids (aldosterone), which help the body retain salt and water ^[7][5]. Young children and infants are especially vulnerable to rapid physical decline during stomach bugs ^[3][8].

What to Expect at the Hospital

When you arrive, hand the staff your emergency letter and tell them your child is at risk for adrenal crisis and needs urgent assessment. Medical guidelines state that treatment must begin immediately and should not be delayed waiting for lab test results ^[9][10].

The hospital care team will focus on stabilizing your child by providing:

• Parenteral hydrocortisone: Hydrocortisone given via IV (intravenously) or IM (intramuscularly) ensures the body gets the urgently required cortisol ^[2][6].
• IV fluids: To treat hypovolemia (too little fluid in the blood circulation) and correct low blood pressure ^[2][11].
• Blood sugar and electrolyte monitoring: Adrenal crises can cause dangerously low blood sugar (hypoglycemia) ^[9]. It can also cause severe electrolyte imbalances, specifically hyponatremia (low blood sodium) and hyperkalemia (high blood potassium) ^[1][12].

Depending on your child’s age, vital signs, and response to treatment, the medical team will determine whether they need to be admitted to the hospital for further observation or if they can safely go home once they can keep oral fluids and medication down ^[1].

Preparing for Emergencies Before They Happen

Because an adrenal crisis escalates quickly, preparation is your best defense. Studies show that parents who receive detailed, hands-on instruction from their healthcare providers feel significantly more capable of managing these emergencies ^[13].

• Check your supplies: Ensure you always have an unexpired, readily available IM hydrocortisone injection kit at home, at school or daycare, and when traveling.
• Practice the injection: Regularly review the injection steps with your endocrinologist so you are confident during an emergency.
• Update your emergency letter: Make sure your medical letter is current, stating your child’s exact IM emergency dose, diagnosis, and endocrinology contact information.
• Follow instructions for other medications: Do not independently increase, stop, or change your child’s fludrocortisone (mineralocorticoid) dose. Always follow your doctor’s written instructions.