What to Do If You Miss a Dose of Hydrocortisone for CAH

Accidentally missing a dose of your daily glucocorticoid (steroid replacement medication, such as hydrocortisone) is a common concern for people managing Congenital Adrenal Hyperplasia (CAH). If you have been prescribed daily hydrocortisone because your body does not make enough cortisol, taking it on schedule is essential to keep you healthy and prevent dangerous complications ^[1].

If you realize you missed a routine dose and you feel well, the general rule is to take the missed dose as soon as you remember it. However, if it is very close to your next scheduled dose, you should skip the missed one and resume your normal schedule ^[2][3]. The exact cutoff for “too close” depends on how many times a day you take your medication, so you must ask your endocrinologist for specific timing rules. You should not double up on your routine doses just to make up for a missed pill. (Note: This is different from “stress dosing” when you are sick, which is discussed below).

Always refer to your personal, written steroid-management plan, as your endocrinologist will have specific instructions tailored to your age, weight, and exact medication schedule ^[2].

Routine Missed Dose vs. Sick-Day Stress Dosing

It is important to distinguish between simply forgetting a pill on a normal day versus missing a dose when you are sick. Fever, infections, injuries, or surgeries cause physical stress that increases your body’s need for cortisol ^[4][5]. During these times, your doctor will likely instruct you to use a “sick-day plan,” which often involves doubling or tripling your normal hydrocortisone dose ^[2]. Never confuse the rule “don’t double up for a missed routine dose” with your doctor’s instructions to take extra medication when you are ill.

Watch for Signs of Low Cortisol

When a dose is missed, delayed, or if you vomit your medication, the amount of cortisol in your body drops. This can lead to symptoms of adrenal insufficiency (a lack of essential steroid hormones) ^[6][7].

Watch out for these warning signs:

• Unusual fatigue, severe lack of energy, or weakness ^[6][7]
• Nausea, poor appetite, or severe stomach pain ^[6][2]
• Repeated vomiting or diarrhea, which can prevent you from absorbing oral pills ^[2][7]
• Dizziness, lightheadedness, or feeling faint (especially when standing), which can be signs of hypotension (low blood pressure) ^[6][8]
• Confusion, unusual sleepiness, shakiness, or a general feeling of being severely unwell ^[8][9]

Emergency Action Plan

If your cortisol levels drop too low, you are at risk for an adrenal crisis, a life-threatening medical emergency where your blood pressure drops dangerously low ^[1][8]. Do not wait for an endocrinology office callback if you are experiencing a crisis.

When to Use Your Emergency Injection and Call 911

You must take immediate action if you:

• Are vomiting repeatedly, have significant diarrhea, or vomit soon after taking your pill (meaning you cannot absorb the hydrocortisone) ^[2][7].
• Feel severely faint, confused, unusually sleepy, or unable to stay awake ^[8][9].
• Experience a seizure or collapse ^[9].

Immediate Steps for a Crisis:

1. Administer the Injection: Immediately use your prescribed emergency hydrocortisone injection kit (an injection into the muscle) according to your written plan ^[2][7].
2. Seek Immediate Help: Call emergency services (like 911) or go directly to the nearest emergency room. Tell them you have Congenital Adrenal Hyperplasia, are in adrenal crisis, and need immediate intravenous (IV, through a vein) fluids and steroids ^[2][7].
3. Do Not Drive: Do not drive yourself if you are faint, confused, or unwell.
4. If No Kit: If you do not have an emergency injection kit or no one is trained to use it, call emergency services immediately and explain that you need emergency hydrocortisone for an adrenal crisis ^[8].

Preparing for the Unexpected

Mistakes happen, which is why preparation is key to staying safe. Patient education and having a concrete action plan are crucial steps in preventing adrenal crises ^[2][3].

• Written Plan: Keep a written sick-day and missed-dose plan from your endocrinology team easily accessible ^[3].
• Medical ID: Always carry a medical alert card or wear a medical ID bracelet that explains your condition, your need for daily hydrocortisone, and that you are at risk for adrenal crisis ^[3].
• Emergency Kit: Ensure your emergency hydrocortisone injection kit is unexpired. Make sure you, your close contacts, and your child’s caregivers or school staff know where it is and how to use it ^[2].