Endocrine / Immunology
Systemic corticosteroids
Glucocorticoids — Powerful anti-inflammatory and immunosuppressant drugs — effective but with important short- and long-term effects.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
What it is
Systemic corticosteroids such as prednisolone are used across medicine to suppress inflammation and immune activity — in asthma and COPD flares, autoimmune and inflammatory conditions, and many other settings. Short courses are common; long-term use needs careful management.
How it works
They mimic the body's own cortisol, switching off many inflammatory genes and damping the immune response. Because the body senses the extra steroid, its own production can shut down — which is why longer courses must not be stopped suddenly.
In practice
In practice the art is using enough to control the disease while planning the exit: short courses can usually stop without tapering, but anything prolonged needs a gradual reduction and "sick day" cover. Anticipate the predictable effects — glucose, blood pressure, mood, infection risk and, long-term, bones — and convert carefully between agents, since potencies differ. Every long-term patient should carry a steroid card.
Examples
Practical use
How to take it & use it well
- Take it in the morning with or after food, as this matches the body's natural rhythm and reduces stomach upset and sleep disturbance.
- Take it exactly as prescribed and do not stop a longer course suddenly, as your body needs time to restart its own steroid production.
- Carry a steroid treatment card or wear an alert if you are on it for more than a short course, and show it to any healthcare professional.
- If you miss a dose, take it as soon as you remember the same day, but do not double up. If you frequently forget, ask for advice.
- Tell your doctor if you become unwell, have an injury or need surgery, as you may need a temporary increase to cope with stress.
- Report signs of infection, mood changes, increased thirst or stomach pain, and have regular reviews for longer courses.
Common uses
- Asthma and COPD exacerbations
- Autoimmune and inflammatory diseases
- Allergic reactions
- Replacement in adrenal insufficiency (hydrocortisone)
Monitoring
- Blood glucose and blood pressure
- Weight, mood and signs of infection
- Bone protection considered for prolonged use
Weighing it up
Advantages & disadvantages
Advantages
- They are powerful at reducing inflammation and calming overactive immune responses.
- They work quickly, which is valuable in flare-ups of conditions like asthma, arthritis and bowel disease.
- They can be life-saving in severe allergic reactions and serious inflammatory illness.
- They come in many forms, so treatment can be matched to the condition.
- Short courses are often very effective with limited risk of long-term side effects.
Disadvantages
- Longer use can cause weight gain, raised blood sugar, raised blood pressure, mood changes and bone thinning.
- They can increase the risk of infections by dampening the immune system.
- They can cause stomach irritation and disturbed sleep.
- They must not be stopped abruptly after a longer course because of the risk of a serious drop in the body's own steroid.
- They can worsen diabetes and blood pressure control.
Key safety principles
What to watch for
- Do not stop longer courses abruptly — taper to avoid adrenal crisis.
- Wide range of effects: raised blood glucose, blood pressure, mood change, infection risk, and with long-term use osteoporosis and weight gain.
- Patients need a steroid treatment card and "sick day" advice if on long-term therapy.
- Different steroids differ in potency — converting between them is a common source of error (see our converter).
Key interactions
What to avoid or check alongside
- Taking them with anti-inflammatory painkillers (NSAIDs) increases the risk of stomach irritation and ulcers.
- They can raise blood sugar and reduce the effect of diabetes medicines and insulin.
- Combining with certain water tablets can lower potassium too much.
- Live vaccines are generally avoided while on higher doses because of the weakened immune response.
- Some medicines that affect the liver can change steroid levels in the body.
- They can reduce the effect of blood pressure medicines by causing fluid retention.
Patient & carer advice
- Carry a steroid card and never stop a long course suddenly
- Take in the morning to mimic the body's rhythm (unless told otherwise)
- Tell any clinician treating you that you take steroids
Use with
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Dose and risk decisions for this class often depend on renal function, weight or bleeding/stroke risk. These tools help:
Answers
Systemic corticosteroids: frequently asked questions
Can I stop taking it suddenly?
Short courses can usually be stopped as directed, but a longer course must be reduced gradually. Stopping abruptly can cause a dangerous drop in your body's own steroid hormone.
Why do I need a steroid card?
If you take steroids for more than a short time, your body relies on the medicine. The card alerts healthcare staff so they can give extra steroid if you are ill, injured or need surgery.
Will it affect my blood sugar?
Steroids can raise blood sugar, which matters if you have diabetes. You may need closer monitoring and temporary adjustments to your diabetes treatment while taking them.
Can I have vaccinations?
Most routine vaccines are fine, but live vaccines are usually avoided on higher doses. Check with your pharmacist or GP before any vaccination.
Is it safe in pregnancy?
Steroids can be used in pregnancy when the benefits outweigh the risks, for example in certain inflammatory conditions. This should be discussed with your doctor.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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