Steroidal anti-inflammatory drugs (SAIDs): powerful control of inflammation, never casual prescribing
In routine clinical use, SAIDs are mainly glucocorticoids (corticosteroids). They suppress inflammation, allergy and immune activity at many levels, and can be life-saving in selected diseases. The same broad action produces important harms: infection, hyperglycaemia, psychiatric disturbance, hypertension, fluid retention, peptic complications, osteoporosis, cataract/glaucoma, growth suppression and hypothalamic–pituitary–adrenal (HPA) axis suppression. The clinical skill is to use the right steroid, route, dose and duration for a defined indication—and to plan monitoring and stopping before prescribing.
Three rules that prevent avoidable harm
- Do not use systemic steroids merely because a patient has “inflammation.” Define the diagnosis, rule out or treat infection, and use disease-specific treatment where available.
- Use the lowest effective dose for the shortest period, preferably as a single morning dose when clinically suitable. Local/topical/inhaled treatment may reduce systemic exposure.
- Never stop prolonged systemic therapy abruptly. Ask about current/recent steroid exposure, give a clear taper/steroid-emergency plan where indicated, and teach the patient when to seek urgent help.
Lesson map
Adrenal physiology, cortisol and HPA axis.
Intracellular receptors, gene regulation, mediator suppression.
Potency, duration, routes and individual agents.
Replacement, anti-inflammatory, anti-allergic and immunosuppressive roles.
Infection, metabolic, bone, eye, neuropsychiatric and adrenal risks.
Selection, monitoring, tapering, cases and OSCE points.
1. What are SAIDs, corticosteroids and glucocorticoids?
- Corticosteroids are steroid hormones made by the adrenal cortex or manufactured as analogues. They include glucocorticoids (principally cortisol-like metabolic, anti-inflammatory and immunoregulatory actions) and mineralocorticoids (aldosterone-like sodium-retaining, potassium-losing actions).
- SAIDs in pharmacology teaching usually means glucocorticoid medicines used to suppress inflammation. They are not the same as anabolic-androgenic steroids used for muscle building.
- Natural glucocorticoids: hydrocortisone (the pharmaceutical form of cortisol) and cortisone. Synthetic drugs: prednisolone/prednisone, methylprednisolone, triamcinolone, dexamethasone and betamethasone.
- Replacement therapy replaces missing cortisol in adrenal insufficiency. Pharmacological therapy uses larger anti-inflammatory/immunosuppressive exposure for another disease. These are different purposes with different risks and stopping rules.
2. Cortisol physiology and the HPA axis: why withdrawal can be dangerous
The hypothalamus releases CRH, stimulating pituitary ACTH; ACTH stimulates the adrenal cortex (zona fasciculata) to produce cortisol. Cortisol normally follows a circadian rhythm—highest in the early morning and lowest around midnight—and rises during severe illness, trauma and surgery. It exerts negative feedback on CRH and ACTH.
| Physiological action of cortisol | Useful survival purpose | What excessive pharmacological exposure produces |
|---|---|---|
| Raises glucose availability through gluconeogenesis and reduced peripheral glucose use | Supplies fuel during stress | Hyperglycaemia, unmasking/worsening diabetes, increased insulin requirement |
| Mobilises amino acids and inhibits protein formation in some tissues | Substrate for acute stress response | Muscle wasting/weakness, thin skin, bruising, poor wound healing and bone loss |
| Changes fat mobilisation and deposition | Energy redistribution | Central/truncal adiposity, moon facies and dorsocervical fat pad |
| Modulates immune and inflammatory reactions | Prevents an excessive inflammatory response | Infection risk and muted fever/inflammatory signs |
| Some mineralocorticoid activity (especially hydrocortisone) | Supports vascular responsiveness and salt-water balance | Oedema, hypertension, hypokalaemia and heart-failure worsening |
HPA-axis suppression
Exogenous systemic glucocorticoid tells the brain that enough cortisol is present. CRH/ACTH fall, endogenous cortisol production is suppressed and the adrenal glands may atrophy. Abrupt withdrawal after clinically significant exposure can leave the patient unable to mount a cortisol response to illness: glucocorticoid-induced adrenal insufficiency. Its features include profound fatigue, nausea/vomiting, abdominal pain, dizziness/postural hypotension, hypoglycaemia and, in severe stress, shock. This is why the duration, dose, route, timing and recent courses must be documented.
3. Mechanism of anti-inflammatory and immunosuppressive action
Glucocorticoids are lipid soluble and enter cells. They bind a cytosolic glucocorticoid receptor; the activated receptor complex moves into the nucleus and alters transcription. Effects develop over hours because many are genomic, although faster non-genomic effects also occur.
| Mechanism | Key molecular consequence | Clinical result |
|---|---|---|
| Transactivation | Increases transcription of anti-inflammatory proteins such as annexin A1 (lipocortin-1), MAPK phosphatase and anti-inflammatory mediators. | Annexin A1 inhibits phospholipase A2, reducing arachidonic-acid release and therefore both prostaglandins and leukotrienes. |
| Transrepression | Interferes with transcription factors such as NF-κB and AP-1; reduces cytokine/chemokine, COX-2, adhesion-molecule and inflammatory-enzyme expression. | Less IL-1, IL-6, TNF and other inflammatory signalling; less leukocyte recruitment and activation. |
| Cellular effects | Reduced macrophage/antigen-presenting cell function, lymphocyte redistribution/apoptosis, reduced eosinophils and reduced capillary permeability. | Rapid reduction in swelling, itch, wheeze and autoimmune tissue injury—but less immune defence. |
| Membrane/vascular effects | Reduced lysosomal enzyme release and inflammatory exudation; increased vascular response to catecholamines. | Less oedema and tissue damage; useful adjunct in selected shock states, never a substitute for cause-specific resuscitation. |
Compare with NSAIDs: NSAIDs mainly inhibit cyclo-oxygenase and prostaglandin formation. Glucocorticoids work upstream at phospholipase A2 and down-regulate COX-2/cytokine genes; therefore they suppress many more inflammatory pathways, including leukotrienes. That greater breadth explains both their power and their wider toxicity. Neither class eradicates an infection or replaces definitive treatment of a surgical problem.
4. Classification: duration, anti-inflammatory potency and mineralocorticoid effect
Exact equivalent doses and preparations vary by product and indication. Learn relative potency and duration; use an approved local formulary for dose conversion.
| Group | Examples | High-yield clinical meaning |
|---|---|---|
| Short acting (about 8–12 h) | Hydrocortisone, cortisone | More mineralocorticoid activity; hydrocortisone is central to adrenal replacement and emergency adrenal-crisis protocols. |
| Intermediate acting (about 12–36 h) | Prednisone, prednisolone, methylprednisolone, triamcinolone | Common systemic anti-inflammatory agents. Prednisone is converted in the liver to prednisolone; consider this in significant hepatic dysfunction. |
| Long acting (about 36–72 h) | Dexamethasone, betamethasone | Very potent glucocorticoid activity with minimal mineralocorticoid effect; longer biological action increases HPA-suppression concern. |
| Predominantly local preparations | Beclometasone, budesonide, fluticasone, mometasone; topical hydrocortisone/betamethasone/clobetasol; ocular and nasal forms | Designed to act at airway, skin, nose, eye, gut or joint. Systemic absorption still matters with high dose, prolonged use, damaged skin, occlusion or interacting medicines. |
Individual medicine profiles
Cortisol analogue with meaningful mineralocorticoid activity. Used in adrenal replacement and urgent stress/adrenal-crisis pathways; can cause salt-water retention at pharmacological doses.
Common oral systemic anti-inflammatory agents. Prednisone requires hepatic activation to prednisolone. Morning dosing is often preferred when appropriate.
Intermediate acting with less mineralocorticoid action than hydrocortisone; used orally or intravenously in selected inflammatory exacerbations and pulse regimens.
Potent, long acting and little mineralocorticoid effect. Used in selected cerebral oedema, antiemetic, severe inflammatory and endocrine testing protocols—do not convert casually.
Potent long acting drug; used in specialist obstetric and inflammatory settings. Follow exact protocol.
Used in selected systemic, topical and intra-articular preparations; injection route does not eliminate systemic effects.
5. Routes of administration: choose the route that treats the site of disease
| Route | Typical role | Safety point |
|---|---|---|
| Oral | Systemic inflammatory/allergic/autoimmune conditions, replacement | Easy to overcontinue. Record indication, start/stop review, duration, interaction and taper plan. |
| IV/IM | Patient cannot take orally, severe acute disease, emergency or specialist protocol | Rapid administration does not remove metabolic, infection or psychiatric risks; reassess conversion to oral/local route. |
| Inhaled | Asthma/COPD controller therapy | Rinse mouth/use spacer as appropriate to reduce oral candidiasis and dysphonia; high dose can have systemic effects. |
| Topical skin | Eczema, dermatitis and other inflammatory dermatoses | Select potency by site, age and diagnosis; avoid prolonged powerful steroid on thin skin/face/flexures unless supervised; infection can be masked or worsened. |
| Intranasal | Allergic rhinitis/nasal polyps | Correct technique reduces epistaxis; local steroid does not provide emergency anaphylaxis treatment. |
| Ophthalmic | Selected inflammatory eye disease under appropriate examination | Can worsen unrecognised herpes/simple bacterial/fungal disease and raise intraocular pressure; do not use blindly in a painful red eye. |
| Intra-articular / soft tissue | Selected inflammatory joint or periarticular disease | Exclude septic arthritis, use sterile technique, counsel on post-injection flare and transient hyperglycaemia; repeated injection needs diagnosis-specific limits. |
6. Clinical indications: use a diagnosis-specific plan
| Clinical setting | Why a glucocorticoid may be used | Critical caution |
|---|---|---|
| Primary/secondary adrenal insufficiency | Physiological cortisol replacement; mineralocorticoid replacement may also be required in primary adrenal failure. | Never confuse replacement with anti-inflammatory dosing. Teach sick-day/stress dosing and emergency plan. |
| Acute asthma/COPD exacerbation | Systemic short course can reduce airway inflammation in indicated exacerbation; inhaled steroid is controller therapy in asthma. | Assess severity, oxygenation and bronchodilator needs; steroid does not replace urgent airway management or antibiotics when a bacterial infection requires them. |
| Severe allergic/inflammatory disease | Can reduce late inflammatory manifestations such as severe urticaria or angioedema under a clinical plan. | Adrenaline is first-line for anaphylaxis; do not delay it for steroid administration. |
| Autoimmune/rheumatic disease | Bridges or controls inflammation in RA, SLE, vasculitis, polymyalgia and other conditions. | Use steroid-sparing disease-modifying treatment whenever indicated; monitor infection, bone and CV risk. |
| Dermatology | Topical/systemic treatment of selected eczema, severe dermatitis, autoimmune blistering disease and other conditions. | Exclude fungal/scabies/bacterial infection and choose potency/site correctly; systemic steroid may cause rebound in some dermatoses. |
| Inflammatory bowel disease / nephrotic or glomerular disease | Induction of remission in selected disease patterns. | Specialist diagnosis, infection screening and monitoring are required; steroids are often not maintenance therapy. |
| Haematology/transplantation/malignancy protocols | Immune cytopenias, lymphoid malignancy regimens, antiemesis and graft-rejection prevention. | Protocol-led treatment; anticipate opportunistic infection, interaction and metabolic toxicity. |
| Cerebral oedema from selected tumours | Dexamethasone may reduce vasogenic oedema and neurological symptoms. | Not routine treatment for all stroke/head injury; use condition-specific neurocritical-care guidance. |
| Obstetrics / neonatal care | Specific antenatal corticosteroid protocols may accelerate fetal lung maturation when preterm birth is likely. | Strict obstetric indication, agent, timing and dose; not a general pregnancy anti-inflammatory medicine. |
7. Adverse effects: relate each to mechanism, dose and duration
Risk rises with higher systemic dose, longer duration, repeated courses, long-acting drugs, concurrent immunosuppression and patient vulnerability. However, even a short course can precipitate hyperglycaemia, mood change, sleep disturbance or infection; local therapy can also cause local and systemic toxicity.
| System | Mechanism / pattern | What to look for and prevent |
|---|---|---|
| Infection / immunity | Suppressed cellular and phagocyte function; inflammatory signs may be muted. | New fever, cough, dysuria, skin lesions or deterioration may be serious. Consider TB, hepatitis, strongyloides and other latent-infection risk before prolonged/intense immunosuppression according to local setting. Avoid inappropriate live vaccines during immunosuppressive exposure. |
| Glucose / metabolism | Gluconeogenesis, insulin resistance and impaired glucose tolerance. | Hyperglycaemia/steroid diabetes, thirst, polyuria. Check glucose and modify diabetes plan; do not assume a known diabetic will remain stable. |
| Muscle / bone / growth | Protein catabolism, reduced osteoblast activity, reduced calcium absorption and increased urinary calcium loss. | Proximal myopathy, osteoporosis/fragility fracture, osteonecrosis, impaired growth and delayed puberty in children. Assess fracture risk; promote weight-bearing measures and use bone-protection strategy when indicated. |
| Fat / appearance | Fat redistribution and appetite/metabolic change. | Weight gain, truncal obesity, moon face, dorsocervical fat pad, dyslipidaemia. Explain before long courses; monitor weight and CV risk. |
| Fluid / cardiovascular | Mineralocorticoid and vascular effects, especially with hydrocortisone. | Oedema, hypertension, hypokalaemia, heart-failure decompensation. Monitor BP, weight/oedema and electrolytes when appropriate. |
| GI | Mucosal repair impairment; risk rises markedly with NSAIDs and other ulcerogenic medicines. | Dyspepsia, ulcer/bleeding/perforation. Review NSAID use, alcohol and ulcer history; gastroprotection is patient-risk based, not automatic for every brief course. |
| Neuropsychiatric | CNS effects may occur early or later. | Insomnia, agitation, anxiety, euphoria, depression, mania, psychosis, cognitive change. Warn patient/family; urgent assessment for severe behavioural change or suicidality. |
| Eye | Lens and intraocular-pressure effects; local ocular effects. | Posterior subcapsular cataract, glaucoma, blurred vision. Seek ophthalmic review for visual symptoms and monitor high-risk long-term patients. |
| Skin / healing | Reduced collagen and immune/inflammatory repair response. | Thin skin, easy bruising, striae, acne, delayed wound healing and infection. Examine skin; avoid needless prolonged potent topical products. |
| Endocrine withdrawal | HPA-axis suppression. | Adrenal insufficiency during sudden cessation or stress. Taper when indicated and provide a steroid emergency/sick-day plan. |
8. Contraindications and precautions: do not memorise a simplistic “never” list
For a life- or organ-threatening inflammatory disease, many conditions listed as “contraindications” are relative risks that require mitigation, specialist advice and monitoring rather than automatic refusal. Important precautions include untreated systemic infection (especially invasive fungal infection), poorly controlled diabetes, active peptic ulcer/bleeding, severe osteoporosis, uncontrolled hypertension/heart failure, glaucoma/cataract risk, psychiatric history, epilepsy, pregnancy, impaired growth, recent exposure to varicella/measles and planned live vaccination. Balance urgency against risk; document the indication and plan.
Infection safety is not optional
Steroids may make a patient feel better while infection progresses. Before prolonged/high-dose systemic treatment, identify current infection and relevant latent-infection risks; obtain disease-specific screening/advice where appropriate. A patient on significant immunosuppression who has fever, progressive breathlessness, confusion or collapse needs urgent assessment—not automatic extra steroid.
9. Important interactions
| Interacting medicine / factor | Why it matters | Practical response |
|---|---|---|
| NSAIDs, aspirin, anticoagulants/antiplatelets | Greater GI ulcer/bleeding risk (and anticoagulant-related bleeding risk). | Avoid unnecessary combination; assess GI and bleeding risk and use gastroprotection when clinically indicated. |
| Diabetes medicines | Glucocorticoids raise blood glucose and can require temporary or major therapy adjustment. | Plan glucose monitoring and prescribe a diabetes-management response, not just “watch.” |
| Diuretics / digoxin | Potassium loss and fluid effects may increase arrhythmia/digoxin toxicity risk. | Check medication list, electrolytes and clinical status. |
| CYP3A4 inhibitors (for example some azole antifungals, macrolides, HIV boosters) | Can increase exposure to many corticosteroids; inhaled/intranasal agents can also become systemic. | Check interaction resource and choose/adjust agent under specialist/pharmacy guidance. |
| CYP3A4 inducers (for example rifampicin, some anticonvulsants) | Can reduce steroid exposure and compromise replacement or disease control. | Do not assume usual dose works; seek regimen-specific advice. |
| Live vaccines | Immunosuppressive steroid doses can allow uncontrolled replication of a live vaccine strain. | Check current/recent dose and vaccine guidance before administration; inactivated vaccines may still be appropriate but response can be reduced. |
10. Safe systemic prescribing, monitoring and stopping
- State the diagnosis and objective: e.g., “induce remission of confirmed inflammatory disease,” not “reduce swelling.” Decide whether a local, inhaled or topical route can achieve the aim.
- Choose the agent deliberately: potency, biological half-life, mineralocorticoid effect, ability to take oral therapy, tissue target and protocol matter.
- Before starting: record BP, weight, glucose/diabetes status, infection history/exposure, medication interactions, mental-health history, ulcer/bleed risk, eye risk and bone/fracture risk. Check relevant baseline tests for expected duration/intensity.
- At every review: confirm benefit, infection symptoms, BP/weight/oedema, glucose, mood/sleep, dyspepsia/bleeding, muscle weakness, fractures/height in children, skin/eyes and adherence/OTC medicines.
- Risk reduction: control diabetes/BP, minimise NSAIDs/alcohol/tobacco, use vaccination/infection-prevention strategy and osteoporosis prevention appropriate to age, dose and duration.
- Plan cessation before the first dose: a short course may simply stop according to its protocol; prolonged or repeated exposure may require tapering. Tapering is individualised by disease control, agent, dose, duration, prior exposure and adrenal-risk assessment—never give a one-size-fits-all schedule.
- Give written patient advice: exact medicine, dose/timing, missed-dose advice, interaction warning, infection/bleeding/mental-health red flags, and a steroid card/emergency plan when indicated.
Morning dosing, alternate-day treatment and tapering—what students should say
A single morning dose may better align with normal cortisol rhythm and can reduce HPA suppression compared with late-day divided exposure when the clinical condition allows. Alternate-day regimens can be used in selected long-term situations but are not suitable for every disease. Tapering is not simply to avoid “withdrawal symptoms”: it allows recovery of endogenous cortisol production while watching for two different problems—return of the underlying disease and adrenal insufficiency. During major illness, trauma or surgery, a patient with adrenal suppression or replacement dependence may need protocolled stress-dose glucocorticoid; this is a medical emergency pathway, not a self-adjustment exercise without guidance.
11. Special populations
Monitor growth, pubertal development, behaviour, glucose and bone health. Use age/weight-specific protocols and avoid unnecessary prolonged systemic therapy.
Do not deny a necessary maternal treatment, but select agent/route/timing with obstetric and disease-specific guidance. Avoid casual systemic treatment.
Expect glucose to rise; make a monitoring and treatment-adjustment plan on day one, especially with high-dose systemic treatment.
Higher risk of osteoporosis, hypertension, diabetes, cataract/glaucoma, infection and polypharmacy. Medication review and bone protection are central.
Risk assessment, targeted screening/prophylaxis and coordination matter before sustained immunosuppression; steroids may still be essential in specific protocolled conditions.
“Local” does not mean harmless. Check technique, duration, site/potency, oral thrush, skin atrophy and interacting medicines.
12. Clinical cases, exam traps and OSCE framework
Case 1: wheeze and collapse after an antibiotic
Do not make IV steroid your first action. Assess airway, breathing and circulation; give intramuscular adrenaline promptly for suspected anaphylaxis and follow emergency protocol. Steroid may have a later adjunctive role but must not delay first-line resuscitation.
Case 2: prednisolone stopped after months of treatment
The patient has vomiting, weakness, dizziness and hypotension during gastroenteritis. Consider adrenal insufficiency/adrenal crisis alongside sepsis and dehydration. Urgent assessment, protocolled hydrocortisone/resuscitation and identification of the prior steroid exposure are required.
Case 3: “simple eczema” worsening on a potent cream
Reassess the diagnosis: tinea incognito, bacterial infection, scabies or allergic contact dermatitis can be masked/worsened by steroid. Examine distribution, ask about duration/quantity/occlusion, treat cause and choose skin-directed therapy correctly.
Case 4: diabetic patient prescribed steroid for an inflammatory flare
Explain that pain may improve but glucose can rise rapidly. Record baseline control, arrange monitoring and coordinate an adjustment plan; do not wait for symptomatic hyperglycaemia.
- OSCE: “How do glucocorticoids reduce inflammation?” They bind intracellular receptors and alter gene transcription: increase anti-inflammatory proteins such as annexin A1, suppress NF-κB/AP-1-driven cytokines and COX-2, reduce phospholipase A2 activity, leukocyte recruitment and vascular permeability.
- OSCE: “Why must long-term therapy not stop abruptly?” Exogenous steroids suppress ACTH and adrenal cortisol production; sudden withdrawal can cause adrenal insufficiency, especially during stress.
- Exam trap: steroids can improve symptoms of infection while impairing host defence; clinical improvement is not proof that infection is controlled.
- Exam trap: a glucocorticoid is not first-line treatment for anaphylaxis, nor does it replace antimicrobial, surgical or disease-modifying therapy.
- Patient red flags: fever/rapid deterioration, black stool or haematemesis, severe abdominal pain, visual change, marked thirst/polyuria, severe mood/behaviour change, new breathlessness/oedema, profound weakness/dizziness after reduction or stopping.
Further study and source trail
Supplied course sources: Steroidal Anti-inflammatory Drugs—SlideShare and Comprehensive Overview of SAIDs and Glucocorticoids—SlideShare. Expand with current NICE oral corticosteroid guidance, SPS corticosteroid monitoring, NHS steroid safety information and the relevant local/specialist protocol. Drug selection, dose conversion, tapering, stress-dose treatment, vaccination and pregnancy management must follow the current condition-specific protocol.
