Corticosteroids, often known as steroids, are an anti-inflammatory medicine prescribed for a wide range of conditions.
They're a man-made version of hormones normally produced by the adrenal glands (two small glands that sit on top of the kidneys).
Corticosteroids are available in different forms, including:
tablets (oral steroids)
injections – which can be into blood vessels, joints or muscles
inhalers – such as mouth or nasal sprays
lotions, gels or creams (topical steroids)
These pages are about steroid tablets, inhalers and injections. Steroid lotions, creams and gels are covered separately.
What are corticosteroids used for?
Corticosteroids are mainly used to reduce inflammation and suppress the immune system.
They are used to treat conditions such as:
allergic rhinitis and hay fever
chronic obstructive pulmonary disease (COPD)
painful and inflamed joints, muscles and tendons
inflammatory bowel disease (IBD) – including Crohn's disease andulcerative colitis
giant cell arteritis and polymyalgia rheumatica
multiple sclerosis (MS)
Corticosteroids can also be used to replace certain hormones that are not being produced by the body naturally – for example, in people withAddison's disease.
Possible side effects
Corticosteroids will only be prescribed if the potential benefits of treatment outweigh the risks. They will also be prescribed at the lowest effective dose for the shortest possible time.
There aren't usually any severe side effects if you take steroid injections, a steroid inhaler, or a short course of steroid tablets. However, prolonged treatment at high doses – particularly with steroid tablets – can cause problems in some people.
Potential side effects of long-term treatment include:
increased appetite – potentially leading to weight gain
thinned skin that bruises easily
increased risk of infections
mood changes, mood swings and depression
high blood pressure
osteoporosis (weak and brittle bones)
withdrawal symptoms caused by suppression of the adrenal glands
If you have troublesome side effects after taking corticosteroids, don't stop taking your medication until your doctor says it's safe to do so, because of the possibility of these unpleasant withdrawal effects.
Your dose may need to be reduced slowly over a few weeks or months, and you may have to have tests to ensure that your adrenal glands are still working properly before stopping corticosteroids altogether, if you have been taking them for a long time.
Cautions and interactions
For most people, including pregnant or breastfeeding women, steroid inhalers and injections are safe. However, they will still only be used if a doctor thinks the potential benefits outweigh the risks.
As steroid tablets are more likely to cause side effects, there are some circumstances when they shouldn't be used or should only be used with caution. These circumstances include:
having an ongoing widespread infection
having mental health or behavioural problems – such as depression or alcohol dependence
having certain underlying physical conditions – such as liver problems, heart failure, high blood pressure or diabetes
taking another medication that may interact with corticosteroids
Corticosteroids can often be taken while you’re pregnant or breastfeeding, although your doctor will only prescribe them if the risks of not being treated outweigh the risks associated with the medication.
Corticosteroids should not be confused with anabolic steroids, which are sometimes used illegally by bodybuilders and athletes to increase muscle strength.
Who can use corticosteroids
For most people, steroid inhalers and steroid injections should not cause any troublesome side effects. Steroid tablets are generally prescribed with more caution, as these can potentially cause more problems.
Corticosteroid tablets are the most powerful type of steroid medication, because they can affect the whole body.
They shouldn't be used if you have an ongoing widespread infection, because they could make it more severe. However, you should continue to take corticosteroids if you develop an infection while already being treated, unless advised otherwise.
Steroid tablets should be used with caution in people with:
liver problems, such as liver disease – corticosteroids may not be broken down by the liver at a normal rate, leading to increased levels of the medication in the blood
mental health or behavioural problems, such as depression or alcohol dependence – corticosteroids can have unpredictable effects on behaviour and mood
wounds – oral corticosteroids can delay wound healing
They should also be used with caution in people with a health condition that could be made worse by taking oral corticosteroids, including:
a recent heart attack
high blood pressure
underactive thyroid gland
In these situations, you will only be prescribed oral corticosteroids if the benefits of treatment clearly outweigh any potential risks.
Most people can safely have corticosteroid injections, but they should be avoided or used with caution if you have an ongoing infection or a blood clotting disorder (such as haemophilia).
Steroid inhalers and sprays
There is generally no reason why someone shouldn't be able to use a steroid inhaler or steroid spray, but these should be used with caution in people with ongoing infections, such as tuberculosis (TB).
Corticosteroids are generally safe to use during pregnancy. However, they're not usually recommended unless the potential benefits outweigh the risks.
For example, steroid tablets may be recommended if you're pregnant and have severe asthma, because the risk to your baby from uncontrolled asthma is higher than from the medication.
There is no evidence that using a steroid inhaler during pregnancy increases the risk of problems such as birth defects, so you can usually continue to use this as normal while you're pregnant.
If a woman needs to take steroid tablets while she is breastfeeding, a type called prednisolone is usually recommended, because it is thought to have the least chance of causing the baby any adverse effects. As a precaution, it's usually recommended that a breastfeeding mother waits three to four hours after taking a tablet before feeding her baby.
Steroid injections, inhalers and sprays are not thought to pose a risk to babies being breastfed.
Medicines that interact with corticosteroids
Corticosteroids can interact with other medicines, and the effects of either medicine can be altered as a result.
There is less chance of this happening with steroid injections or sprays, although it can occasionally happen if they're used at high doses and for a long time.
Some of the more common interactions are listed below, but this is not a complete list. If you want to check your medicines are safe to take with corticosteroids, ask your GP or pharmacist, or read the patient information leaflet that comes with your medicine.
You can also search for your medication in the Medicines A-Z guide.
Anticoagulant medicines are medications that make the blood less sticky. They are often prescribed to people with a history of blood clotsor an increased risk of developing them.
Combining corticosteroids with anticoagulant medicines can sometimes make anticoagulants less effective. Alternatively, it can increase their blood-thinning effect, which can cause bleeding inside the digestive system.
Anticonvulsants are medicines used to prevent seizures (fits) and are often used to treat epilepsy, but they can reduce the effectiveness of corticosteroids.
Depending on how frequent and severe your seizures are and the condition the steroids are being used to treat, you may be advised to temporarily stop taking anticonvulsants.
Corticosteroids can decrease the effectiveness of medications used to treat diabetes.
If you need to take both of these medications, your blood glucose levels will usually be checked more regularly and your dose of diabetes medication may need to be adjusted.
Corticosteroids, including steroid inhalers, can sometimes interact with a type of medication known as protease inhibitors (such as ritonavir) used to treat HIV.
The HIV medication may increase the level of corticosteroid in your body, which might increase your risk of experiencing side effects.
Some vaccinations contain a weakened form of the infection they are designed to protect against. These are known as live vaccines. Examples of live vaccines include:
the measles, mumps and rubella (MMR) vaccine
the BCG vaccine for tuberculosis (TB)
As corticosteroids can weaken your immune system and make you more vulnerable to infection, you should avoid any live vaccine until at least three months after your course of corticosteroids has finished.
Non-steroidal anti-inflammatory drugs
Non-steroidal anti-inflammatory drugs (NSAIDs) are a group of commonly used painkillers, such as ibuprofen, that are available over the counter at pharmacists.
Combining NSAIDs and corticosteroids can increase your risk of developing stomach ulcers and internal bleeding. If you need to take both medications, you may be given an additional medication called a proton pump inhibitor (PPI) to reduce the risk of stomach ulcers.
Side effects of corticosteroids
Corticosteroids are powerful medications that can sometimes have a wide range of side effects.
They will only be used if the potential benefits are thought to outweigh this risk.
The risk of experiencing side effects largely depends on:
the type of steroid you're taking – steroid tablets (oral corticosteroids) are more likely to cause side effects than inhalers or injections
the dose – the higher the dose, the greater the risk of developing side effects
the length of treatment – for example, you're more likely to develop side effects if you take steroid tablets for more than three weeks
your age – young children and the elderly are more likely to experience side effects
Some of the main side effects are listed below, but this is not a complete list. To learn about all the possible side effects of your medication, read the patient information leaflet that comes with it or search for your medication in the Medicines A-Z guide.
Inhaled steroids usually have few or no side effects if used at normal doses. However, they can sometimes cause:
a sore mouth or throat
difficulty speaking or a hoarse or croaky voice
Rinsing your mouth out with water after using your medication can help to prevent oral thrush, and using a device called a spacer with your medication can help to prevent many of the other problems.
There is also some evidence that steroid inhalers used by people withchronic obstructive pulmonary disease (COPD) can increase the risk of chest infections such as pneumonia. Discuss this with your health professional if you’re concerned.
Inhaled steroids at high doses can sometimes cause some of the more serious side effects that are more often linked with steroid tablets (see below), but this is rare.
Steroids that are injected into muscles and joints may cause some pain and swelling at the site of the injection. However, this should pass within a few days.
Steroid injections can also cause muscle or tendon weakness, so you may be advised to rest the treated area for a few days after the injection. Other possible side effects can include infections,blushing, and thinning and lightening of the skin in the area where the injection is given.
Because of the risk of side effects, steroid injections are often only given at intervals of at least six weeks and a maximum of three injections into one area is usually recommended.
Steroids that are injected into a blood vessel (intravenous steroids) may sometimes cause some of the more widespread side effects described below.
Short, occasional courses of steroid tablets taken for no longer than three weeks are very unlikely to cause troublesome side effects.
It’s sometimes necessary, however, for them to be taken for longer periods. In these cases, you’re more likely to develop troublesome side effects, although this is not inevitable.
Steroid tablets taken for longer than three weeks can potentially cause:
increased appetite – which can potentially lead to weight gain if you find it difficult to control what you eat
rapid mood swings and mood changes – such as becoming aggressive, irritable and short-tempered with people
thin skin that bruises easily
delayed wound healing
a combination of fatty deposits that develop in the face, stretch marks across the body and acne – known as Cushing’s syndrome
weakening of the bones (osteoporosis)
diabetes (or they may worsen existing diabetes)
high blood pressure
glaucoma and cataracts (eye conditions)
stomach ulcers – you may be prescribed an additional medication called a proton pump inhibitor (PPI) to reduce this risk
mental health problems, such as depression, suicidal thoughts,anxiety, confusion and hallucinations – see your GP if you experience any of these problems
increased risk of infections, particularly chickenpox, shingles andmeasles – avoid close contact with anyone who has an infection and seek medical advice immediately if you think you may have been exposed
reduced growth in children
Most side effects should improve if you're able to reduce your dosage or eventually stop taking the medication.
You may have regular checks and tests for conditions such as diabetes, high blood pressure and glaucoma if you need to take steroid tablets on a long-term basis.
Reporting side effects
The Yellow Card Scheme allows you to report suspected side effects from any type of medicine you are taking. It is run by a medicines safety watchdog called the Medicines and Healthcare products Regulatory Agency (MHRA).
See the Yellow Card Scheme website for more information.