What are corticosteroids?


Don’t worry, we’re not talking about the anabolic steroids some athletes and bodybuilders illegally take to enhance performance. Corticosteroids are a completely different type of steroid. These are among the most widely prescribed drugs in the world. And one of the many things they’re used for is treating allergy symptoms. Read on to find out how and why.

How do corticosteroids work?

Corticosteroids mimic hormones made by your body. They’re anti-inflammatory and help manage conditions caused by an overactive immune system. That includes eczema (atopic dermatitis) and allergic rhinitis caused by hay fever and other allergies – for instance to house dust mites. Corticosteroids are also an important part of managing advanced respiratory illnesses. Using corticosteroids to boost your natural hormone levels can help to ease these symptoms.

What should I look out for?

Confusingly, corticosteroids are referred to by several names; glucocorticosteroids, glucocorticoids and even just steroids. They also come in different forms and strengths. The local pharmacy can usually sell you the mildest versions over the counter. Otherwise you’ll need to visit your health care provider and get a prescription. Speak to your health care provider or pharmacist before taking corticosteroids.

Topical corticosteroids are designed to treat one specific part of your body. They’re often – but not always – applied externally:

  • Nasal sprays for people with allergic rhinitis
  • Inhalers to manage advanced respiratory illnesses
  • Creams, lotions and ointments to treat skin affected by eczema

There are also systemic corticosteroids. These are taken internally, as pills or injections, and affect the whole body. Systemic treatments are usually prescribed in more severe cases.


Corticosteroids mimic hormones made by your body. These medicines play a big part in controlling allergy symptoms and many other health conditions.

Corticosteroids for hay fever

Hay fever is an allergic reaction to pollen. Your immune system thinks the tiny particles are a threat. It releases histamine as a defense – and this makes the lining of your nose swell up. To you, that feels like a stuffy, itchy or runny nose.

Antihistamines are perhaps the most common treatment. But corticosteroid nasal spray is also a first-in-line option especially when it comes to persistent symptoms. And research has actually shown that for some people combination therapy – using antihistamine and corticosteroid nasal sprays – might be the way to go in dealing with symptoms of hay fever.

The way to spray: how to use a corticosteroid nasal spray

Corticosteroid nasal sprays can help ease symptoms of allergies, for example to dust mites, pets and pollen. We’ve put together these top tips to help you use yours as effectively as possible.

  • You may find it can take from a few days to up to two weeks to notice any benefit.
  • So start using the corticosteroid spray two weeks before you expect to get symptoms. For instance, you can check a pollen calendar to see when the flowering season for specific pollen types starts.
  • Gently blow your nose to remove some of the mucus. You can also use a nasal douche.
  • Then wash your hands before using the nasal spray.
  • Tip your head forward to help the spray get to the right part of your nose.
  • Put the end of the spray bottle just inside one of your nostrils.
  • Pointing towards your ear or your eye, press down on the pump as many times as the spray instructions say.
  • Do not sniff – that could draw the medicine into your throat when it’s needed in your nose.
  • Repeat with the other nostril.
  • Use your corticosteroid nasal spray regularly when needed, for example throughout your personal pollen season.
  • It could be in the morning, or evening, or both; follow the instructions for your corticosteroid nasal spray.

Of course, always read the information leaflet and carefully follow the instructions for your corticosteroid nasal spray, as they might differ from these general tips. And if in doubt ask your health care provider or pharmacist.

Did you Know...?

  • Corticosteroids are man-made versions of cortisol, which is a stress hormone.
  • Your body releases cortisol as part of the fight-or-flight mechanism when you’re afraid.
  • But cortisol does lots of other jobs around the body: regulating your metabolism, blood pressure and bone formation.
  • Corticosteroids are anti-inflammatory and help to suppress your immune system when it’s overacting.
  • In 1950 the Nobel Prize for Medicine and Physiology was awarded to Edward Calvin Kendall, Tadeusz Reichstein and Philip Showalter Hench for their groundbreaking work with this hormone.

Corticosteroids inhalers

Most people with advanced respiratory illnesses use a corticosteroid inhaler every day to keep the inflammation of their airways under control. There are two types; to relieve symptoms (reliever/rescue inhalers) and to prevent them in the first place (preventer/controller inhalers). Some corticosteroid inhalers combine the two (combination inhalers). Without them, the life of people withthese conditions would be dramatically different – and very restricted.

Corticosteroids for eczema

Eczema is another chronic condition for which corticosteroids are the main treatment. There’s no cure yet but eczema can improve or even clear completely in some children as they get older. It can show up as small patches of dry cracked skin, but some people are itchy, sore and red all over the body. Eczema is always hard to live with.

Fortunately, corticosteroid creams can help to soothe the skin and control inflammation. Eczema is also known as atopic dermatitis. Many other types of dermatitis and skin rashes respond to corticosteroid creams too.

Antihistamines for allergy symptom relief

Also need to know about

Can children use corticosteroids?

Strong corticosteroids are not usually given to young children. Otherwise, steroids are an important part of the treatment for allergic rhinitis and eczema in childhood. Of course there can be side effects, which we’ll talk about next. But if you follow your health care provider’s prescription, and your child’s condition and response is monitored, these medicines can be taken by children. Don’t use corticosteroids for your child without your health care provider’s guidance.

What are the side effects of corticosteroids?

Like any medicine, corticosteroids can cause side effects. And also like any medicine, they come with an information leaflet. Make sure to read it before you start tackling your allergy symptoms.

Corticosteroids can have local or systemic side effects. Systemic means they impact on the whole body. Topical formulations like nasal sprays, inhalers and creams tend to be prescribed before pills or injections because the intended effects are mostly concentrated at one site. So the chances of systemic side effects are much lower. Corticosteroids are usually recommended for use at the lowest effective dose for the shortest possible time.

Local side effects of corticosteroids

Corticosteroid nasal sprays, inhalers and topical creams usually cause no significant side effects if used correctly.

Here, we list some of the side effects you could experience. Consult the information leaflet for your medication for specific details.

Local side effects of corticosteroid nasal sprays can include:

  • Nasal irritation such as stinging, dryness, itchiness and swelling
  • Dry throat
  • Nasty taste in your mouth
  • Nosebleeds because corticosteroids can thin the skin

Local side effects of corticosteroid inhalers can include:

  • Sore mouth or throat
  • Croaky voice
  • Cough
  • Oral thrush
  • Nosebleeds because corticosteroids can thin the skin

Local side effects of corticosteroid creams can include:

  • A stinging and burning sensation as you rub the cream in (usually stops once you’ve been using the medication for a while)
  • Less common: changes in skin color and other reactions like acne or reddening (rosacea)

Systemic side effects of corticosteroids

All corticosteroids can have side effects across your whole body. This goes not only for pills and injections, but also for nasal sprays, inhalers and creams even though they might only be applied to one small area. The chance of systemic side effects goes up with these topical corticosteroids if you use them at a high dose for a long time. Luckily, this is much less common than with tablets.

Always consult the information leaflet for the medication you’re taking for specific side effects.

Systemic side effects of corticosteroids from long-term treatment can include:

  • Increased appetite
  • Acne
  • Thinned skin that bruises easily
  • Increased risks of infections
  • Mood changes, mood swings and depression
  • Diabetes
  • High blood pressure
  • Weak and brittle bones (osteoporosis)
  • Growth problems in children
  • Withdrawal symptoms caused by suppression of the adrenal glands

What are the symptoms
of allergic rhinitis?

Young man blowing his nose because of allergic rhinitis symptoms

Your health care provider will usually monitor you closely if you, for example, use a corticosteroid inhaler daily. Always talk to them about how to take your medication and don’t stop taking it before your health care provider says it’s safe to do so.

Be safe, be sensible when taking corticosteroids with other medication

Always speak to your doctor or pharmacist if you’re already on medication and consider using corticosteroids. They can interfere with how other drugs work, and vice versa. You’ll find all these details on the information leaflet that comes with the corticosteroid.

Living with corticosteroids

As you can see, corticosteroids play a big part in controlling allergy symptoms. But they have a wider use too. Corticosteroids are prescribed to manage medical conditions including rheumatoid arthritis, inflammatory bowel disease and multiple sclerosis. If not a miracle cure, they are certainly a way of improving the lives of a huge number of people.

What if regular allergy meds are not enough?

Corticosteroids as well as other allergy relief meds and control measures may not be able to keep your allergy symptoms in check. If so, your health care provider might discuss allergy immunotherapy with you.

Immunotherapy goes straight to the cause of your allergies. The idea is to desensitize your immune system through very small doses of an allergen given as shots or tablets. Your body gradually learns not to go on high alert each time you encounter the substance in real life. Immunotherapy can help reduce your symptoms and the need for medication to relieve them.

Allergy control checker

How well do you feel your symptoms are under control? Try this quick questionnaire to find out.
Young woman holding a small dog that might be causing her allergy symptoms
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