Reviewed by MedNext Clinical Team
Prednisolone and other systemic corticosteroids are among the most frequently prescribed drugs in medicine. Their potent anti-inflammatory and immunosuppressive effects make them indispensable in conditions ranging from acute severe asthma to organ transplantation. However, their side-effect profile — particularly with prolonged use — demands careful risk-benefit assessment, appropriate monitoring, and structured patient education [1].
Mechanism of Action
Corticosteroids bind to intracellular glucocorticoid receptors, which then translocate to the nucleus and modulate gene transcription. This suppresses the production of pro-inflammatory cytokines (e.g., IL-1, IL-6, TNF-alpha), inhibits phospholipase A2 (reducing prostaglandin and leukotriene synthesis), and impairs the migration and function of immune cells. The result is broad anti-inflammatory and immunosuppressive activity [1].
Short Courses
Short courses of prednisolone (typically 5–14 days) for conditions such as acute asthma exacerbations, allergic reactions, or inflammatory flares generally do not require tapering if the total duration is less than three weeks. However, even short courses can cause mood changes (euphoria or depression), insomnia, increased appetite, and transient rises in blood glucose — particularly relevant in diabetic patients who should be counselled to monitor their blood sugar more closely.
Adrenal Suppression and Tapering
Prolonged use (generally more than 3 weeks, or any dose taken at night) suppresses the hypothalamic-pituitary-adrenal (HPA) axis. Abrupt withdrawal after long-term therapy risks adrenal crisis — a life-threatening emergency. Tapering protocols vary by duration of therapy, dose, and indication, but the general principle is to reduce the dose gradually to allow HPA axis recovery. Patients on long-term steroids should carry a steroid emergency card and be counselled about sick-day rules (typically doubling the dose during febrile illness).
Metabolic Effects
- Hyperglycaemia: Corticosteroids cause insulin resistance and increase hepatic glucose output. Monitor blood glucose in all patients, and consider initiating or intensifying diabetes treatment when steroid courses are prolonged.
- Hypertension: Sodium and water retention contribute to raised blood pressure with long-term use.
- Weight gain and Cushingoid features: Central obesity, moon face, and buffalo hump may develop with prolonged therapy.
- Dyslipidaemia: Elevated triglycerides and LDL cholesterol with long-term use.
Osteoporosis Prevention
Glucocorticoid-induced osteoporosis is the most common iatrogenic cause of osteoporosis. Any patient commencing systemic corticosteroids likely to be taken for 3 months or longer should receive bone protection. Current guidance recommends calcium and vitamin D supplementation for all such patients, and a bisphosphonate (e.g., alendronic acid) for patients above a defined fracture risk threshold. Baseline DEXA scanning should be considered in high-risk patients.
Other Significant Risks
Long-term corticosteroids also increase the risk of infection (including reactivation of latent tuberculosis and opportunistic infections), cataract formation, glaucoma, avascular necrosis of the femoral head, skin thinning, and impaired wound healing. Patients should be screened for latent TB before initiating long-term treatment.
Steroid Alert Cards
All patients on long-term systemic corticosteroids should be issued a steroid treatment card and, if the course is expected to exceed 3 months, a steroid emergency card. These alert healthcare professionals to the risk of adrenal suppression in the event of illness, trauma, or surgery [1].
References
- Rhen T, Cidlowski JA. Antiinflammatory action of glucocorticoids — new mechanisms for old drugs. NEJM. 2005;353:1711-1723.