9. Other Conditions and Drug Interactions
Often people diagnosed with adrenal insufficiency also suffer from other conditions or diseases that require treatment.
9.1. Drug interactions
Drug interactions occur when a drug interacts or interferes with another drug. This can alter the way the drug(s) act(s) in the body (e.g. by increasing or decreasing the effect of one or both of the drugs) or cause unexpected side effects.
For people with adrenal insufficiency, taking drugs that influence the glucocorticoid metabolism may require an adjustment of their daily hydrocortisone dose.
Some drugs, such as antiretroviral drugs, delay metabolism and therefore lead to an increased glucocorticoid concentration in the blood. Other drugs accelerate glucocorticoid metabolism and therefore reduce their effect. Examples for those are anticonvulsants / antiepileptica (eg. phenytoin, carbamazepine), antituberculosis medicine (eg. rifampicin) and antifungals (eg. ketoconazole).
Other drugs (NSAIDs, some antidepressants and some antibiotics) influence electrolyte levels and blood pressure and may require an adjustment of the fludrocortisone dose.
Diuretics and acetazolamide should be avoided unless clearly indicated.
9.2. Autoimmune Diseases / Polyendocrine Deficiency Syndrome
In 40% of people living with Addison’s disease (autoimmune adrenalitis/primary adrenal insufficiency (see primary adrenal insufficiency, PAI) only the adrenal glands have ceased hormone production. More often, other glands are affected as well. This is called polyendocrine deficiency syndrome and classified into two separate forms, referred to as type I and type II.
Type I typically occurs in children and adrenal insufficiency may be accompanied by underactive parathyroid glands, slow sexual development, pernicious anaemia, chronic candida infections, chronic active hepatitis, and, in very rare cases, hair loss.
Type II is often called Schmidt’s syndrome and affects adults in the 3rd to 4th decade of life. Symptoms may include an underactive thyroid gland, slow sexual development, diabetes mellitus and/or vitiligo (a loss of pigment on areas of their skin).
Schmidt’s syndrome is believed to be inherited because frequently more than one family member tends to have one or more (but not always the same) endocrine deficiencies.
More information on Autoimmune Polyendocrine Syndrome Type II can be found on the Website of the National Organization for Rare Disorders, Inc. (USA, information last updated in 2007).
9.3. Steroid Therapy and Adrenal Suppression
Over the past decades, an increase in the total number of people diagnosed with adrenal insufficiency has been observed and attributed to the long-term use of steroids to treat chronic conditions (= secondary adrenal insufficiency, see also types of adrenal insufficiency)
Although considered rare in the past, the number of people with secondary adrenal insufficiency is rising rapidly and now outweighs the incidence of primary adrenal insufficiency (Addison’s) by 2:1.
Steroids (usually prednisone) are commonly used to treat conditions such as rheumatoid arthritis, asthma or ulcerative colitis. Although essential in the treatment of those disorders, taking any steroids for longer than two weeks may lead to a suppression of cortisol production (see also HPA, negative feedback loop) in the adrenal glands, eventually causing adrenal insufficiency.
Short-term treatments, e.g. steroids given over 3 days, do not pose a significant risk.
Every person on long-term steroid treatment needs to know that any acute illness (e.g. a fever), accident, procedure (e.g. colonoscopy) or surgery require taking additional cortisone (“Stress-dosing“) to avoid an adrenal crisis. They also need to be able to recognise low cortisol symptoms and should never abruptly discontinue steroid treatment, as this can lead to an adrenal crisis.
Instead, a gradual reduction in dosage (tapering/weaning off) under medical supervision may give the adrenal glands time to resume their normal function. How long it will take to taper off depends on the condition being treated, the dose and duration of use and other medical considerations. A full recovery can take anywhere from a week to several months or even years. Unfortunately, the suppression of endogenous cortisol production cannot always be reversed, therefore leading to secondary adrenal insufficiency.
For more information on adrenal suppression, click here.
DON’T FORGET!Any long-term steroid treatment can cause adrenal insufficiency!
Taking prednisone or other steroids as tablets is not the only way to develop adrenal insufficiency. Inhaled or locally injected steroids as well as creams are equally potent and may suppress cortisol production in the adrenal glands (🡺 HPA, negative feedback loop).
• Hydrocortisone / prednisone tablets
• Inhaled asthma steroids eg. Symbicort, Seretide
• Intravenous steroids eg. methylprednisolone
• Joint and muscle steroid injections
• Steroid creams for skin conditions
There is a chance of causing adrenal suppression by taking as little as 5mg of prednisone, or 20mg of hydrocortisone, for 3 or more weeks. The longer the steroids are taken, or the higher the dose, the greater the chance.
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Anatomy/Physiology | Types of Adrenal Insufficiency | Symptoms | Testing/Diagnosis | Treatment | Stress dosing/Sick day Management | Adrenal Crisis | Quality of Life and Risks | Other Conditions and Drugs | Long-term Management | Suggested Reading | Literature/References
Author: Gisela Spallek, MD PhD
Edited by Maria Stewart, Director of AIC and deputy editor Des Rolph, Associate Director of AIC