Updated: 15/03/2020

Watch our latest video on management of Addison's medication when you have COVID-19 from Professor Simon Pearce.

People with adrenal insufficiency are particularly vulnerable to adrenal crisis being triggered by seemingly "minor" ailments, including vomiting, diarrhoea, colds & flu. It's important to recognise the early symptoms of a bug or cold and adjust your steroid replacement medication accordingly.

These are the common triggers or causes of adrenal crisis :

adrenal crisis triggers

These rules of thumb are known as the "sick day rules". On days where you are feeling off-colour, injured or ill, follow these rules to keep safe and minimise the chances of an adrenal crisis.

Please note: During illness please keep taking your tablets. Our medics have confirmed that rumours and reports of our doses making people with Addison's Disease immunosuppressed have been vastly over-exaggerated. 

If you are feeling unwell or have an accident

You should double your daily hydrocortisone or prednisolone dose if:

  • You get an infection with a temperature of 38.0 degrees Celsius  or higher
  • You get a bad cold, ‘flu, diarrhoea or other infection that makes you feel poorly or weak
  • You break a bone or suffer from any similar significant injury

Minimum doses

For hydrocortisone users :

  • If you take less than 20mg of hydrocortisone in total as your regular daily dose, go up to 40mg daily as a minimum hydrocortisone dose during stress and illness.

For prednisolone users :

  • If you take less than 5mg of prednisolone in total as your regular daily dose, go up to 10mg daily as a minimum prednisolone dose during stress and illness.


  • Keep your dose of steroids doubled for 2 days and then go back to your usual dose, provided that you now feel better.
  • If you don’t feel better after 48hrs, keep your steroid dose doubled and seek advice from your GP or your endocrine nurse or doctor.
  • If you are prescribed antibiotics for an infection, double your hydrocortisone dose until you finish the course, or feel completely back to normal.

Becoming more ill

If you get a severe infection with a temperature above 40.0 degrees Celsius, then you need to take 3 times your normal hydrocortisone dose and seek advice from your doctor immediately. This could be the start of an adrenal crisis.

If you vomit back your medication within 30 minutes of taking it, take a double dose again immediately. If you vomit this second dose back, then inject yourself with 100mg of hydrocortisone and seek advice.

If you carry on vomiting, you will become dehydrated and this will develop into an adrenal crisis unless you go to hospital for a saline drip.

Note: If you up your dose higher than 50mg of Hydrocortisone due to illness, you don't need to take your Fludrocortisone at this time. This is because Hydrocortisone has some mineralcorticoid effect. Be sure to start it again once you taper back down.

Read our advice about Coronavirus.