Corticosteroids are synthetic drugs that are used to treat a wide variety of disorders, including asthma, arthritis, skin conditions and autoimmune diseases. The drug mimics cortisol, a hormone that's naturally produced by the adrenal glands in healthy people.
Cortisol, commonly called the "stress hormone," is a steroid hormone (not to be confused with anabolic steroids, which are sometimes abused by athletes) that's released in response to stress. It's involved in a wide range of processes in the body, such as metabolism, inflammation, blood pressure regulation and bone formation, according to Johns Hopkins Medicine.
Corticosteroids work by decreasing inflammation and suppressing the immune system, according to Cleveland Clinic. Left untreated, excess inflammation can damage healthy tissue, as well as cause redness, swelling and pain.
The first use of corticosteroids dates back to 1948, when rheumatologists at the Mayo Clinic treated a patient who had debilitating rheumatoid arthritis, according to a 2010 article published in the journal Clinical Chemistry. The patient, who was treated with the then-experimental injectable drug, was able to walk out of the hospital after the third treatment and go on a 3-hour shopping spree, according to the author.
There are several types of corticosteroids, including cortisone, prednisone, dexamethasone, prednisolone, betamethasone and hydrocortisone. Cortisone was the first corticosteroid drug approved for use in the U.S., which happened in 1950, according to the U.S. National Institutes of Health.
Corticosteroids are often used as a anti-inflammatory medications and immune suppressants to treat arthritis, asthma, autoimmune diseases (including lupus and multiple sclerosis), skin conditions (such as eczema and psoriasis), some types of cancer (such as leukemia), and the aftermath of organ transplant, according to the U.S. National Library of Medicine.
Depending on the specific treatment goal of the drug, it may be used orally, injected, inhaled or applied topically, according to the Mayo Clinic. Oral corticosteroids are typically used to treat and help control symptoms of chronic conditions, such as rheumatoid arthritis, by reducing inflammation throughout the body. Injected corticosteroids treat a specific location, such as inflammation or pain caused by tendinitis in a joint.
Corticosteroids are inhaled to treat asthma by reducing inflammation and swelling of the airways, and they can also help lower the risk or frequency of future attacks. Topical steroids are usually put into creams and ointments to treat and soothe skin conditions.
The immunosuppressive properties of corticosteroids are useful in treating diseases, such as lupus, in which the body's immune system can't properly distinguish between healthy cells and harmful ones. The drugs can also be beneficial in reducing the risk of rejection of a newly transplanted organ.
Corticosteroids are often used in conjunction with other treatments of lymphoid cancers, leukemia and tumors, where inflammation is a primary symptom, according to a 2016 article published in the journal Steroids. The corticosteroids prevent white blood cells from traveling to the site of inflammation, decreasing the swelling around tumors and the pressure on nerve endings to relieve pain, according to Chemocare. Corticosteroids are also prescribed to lessen the effects of chemotherapy symptoms such as nausea, vomiting and diminished appetite, although how the drugs work in those instances isn't fully understood.
Risks of corticosteroids
Although corticosteroids are effective medications, they can also have serious side effects.
For oral corticosteroids, these side effects may include glaucoma, fluid retention, high blood pressure and weight gain, according to the Mayo Clinic. There can even be psychological effects, including mood swings, confusion and behavior changes, the Mayo Clinic said. Taking the medication long term can also lead to cataracts, high blood sugar and diabetes, increased risk of infection from common bacteria and viruses, osteoporosis, suppressed adrenal-gland hormone production, and thin skin that has higher rates of bruising and slower wound healing.
When inhaled, corticosteroids may cause oral thrush (a fungal infection in the mouth) and hoarseness. These side effects are typically caused when some of the drug lingers in the mouth and throat after inhalation, instead of traveling to the lungs. The risk is typically minimized by rinsing and gargling with water, without swallowing, to clear any residual medication.
Application of topical steroids may lead to thin skin, red skin lesions and acne at the application site in some instances, according to the Mayo Clinic.
The side effects of injected corticosteroids may include temporary skin thinning, skin color loss and intense pain at the injection site, as well as facial flushing, insomnia and high blood sugar.
If a regiment of corticosteroids is prescribed by a doctor, there are ways to help minimize side effects. Patients should be sure to take the medication exactly as prescribed, eat a healthy diet with limited fat and salt and plenty of calcium and vitamin D, and exercise regularly to maintain strong bones and muscles, according to the University of Washington Orthopaedics and Sports Medicine.
Withdrawal symptoms may also occur if the medication is stopped suddenly or reduced too quickly. These can include muscle, bone and joint pain, nausea, weight loss and headache.
Long term use of corticosteroids may alter normal hormone production. For that reason, doctors may advise their patients to wear a medical bracelet or tag so that other medical professionals are aware of the patient's' corticosteroid use, and will alter treatment accordingly.
- Learn more about the history of clinical research on corticosteroids from the National Institutes of Health.
- See the definition of corticosteroids and a list of inhaled corticosteroid medications from the American Academy of Allergy, Asthma and Immunology.
- Find out more about corticosteroids from the U.S. National Library of Medicine.
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Rachel Ross is a science writer and editor focusing on astronomy, Earth science, physical science and math. She holds a Bachelor of Arts in Philosophy from the University of California Davis and a Master's degree in astronomy from James Cook University. She also has a certificate in science writing from Stanford University. Prior to becoming a science writer, Rachel worked at the Las Cumbres Observatory in California, where she specialized in education and outreach, supplemented with science research and telescope operations. While studying for her undergraduate degree, Rachel also taught an introduction to astronomy lab and worked with a research astronomer.