Dexamethasone (Decadron)

• Core Use: High-potency, long-acting glucocorticoid with strong anti-inflammatory and anti-edema effects; minimal mineralocorticoid activity
• Common Applications: Cerebral edema from brain tumors/metastases, airway edema (post-extubation, croup, anaphylaxis adjunct), ARDS/COVID-19 pneumonia, antiemetic adjunct
• Half-Life: Biologic half-life ~36–72 hours; once-daily dosing often sufficient
• Key Advantage: Strong glucocorticoid effect without significant sodium/water retention (preferred for cerebral edema and neuro cases)
• Key Danger: Hyperglycemia, infection risk, myopathy, delirium, and adrenal suppression with prolonged use; HPA-axis suppression more pronounced than with hydrocortisone
• Special Note: Short courses relatively safe; prolonged/repeated high doses require careful risk-benefit assessment

• Generic Name: Dexamethasone
• Brand Names: Decadron, Ozurdex (ophthalmic), many generics

Long-acting systemic glucocorticoid; minimal mineralocorticoid activity

Mechanism of Action:

• Synthetic glucocorticoid that diffuses into cells and binds cytosolic glucocorticoid receptors; the complex translocates to the nucleus and alters transcription of numerous genes
• Downregulates pro-inflammatory cytokines (e.g., IL-1, IL-6, TNF-α), adhesion molecules, and COX-2, while upregulating anti-inflammatory mediators
• Stabilizes lysosomal and cellular membranes, reduces capillary permeability, and decreases leukocyte migration into inflamed tissues, limiting edema and tissue damage
• Minimal mineralocorticoid activity means little direct effect on sodium retention or potassium excretion compared with hydrocortisone or fludrocortisone
• In cerebral edema from tumors or metastases, decreases vasogenic edema by reducing capillary permeability in tumor-associated vasculature, thereby lowering intracranial pressure over hours–days

Pharmacokinetics:

• Routes: IV, IM, PO; oral bioavailability is high (~80–90%), allowing easy IV↔PO transitions when gut is functional
• Onset: Anti-inflammatory effect begins within several hours; for airway edema (e.g., croup, post-extubation), clinical improvement often seen within 4–8 hours
• Distribution: Widely distributed, including CNS; highly protein bound; crosses placenta and enters breast milk
• Metabolism: Predominantly hepatic (CYP3A4) to inactive metabolites
• Elimination: Metabolites primarily renal; elimination half-life ~3–5 hours, but biologic half-life is long (36–72 hours), reflecting prolonged genomic effects
• Steroid Potency Equivalence: 0.75 mg dexamethasone ≈ 5 mg prednisone ≈ 20 mg hydrocortisone

• Cerebral edema due to brain tumors and metastatic lesions; occasionally used as adjunct in bacterial meningitis (selected cases, e.g., pneumococcal meningitis when given early)
• Airway edema: croup, post-extubation stridor, anaphylaxis adjunct (after epinephrine), upper airway trauma/inflammation where airway compromise is a concern
• ARDS and severe COVID-19 pneumonia: systemic anti-inflammatory effect to blunt lung injury and improve outcomes in selected patients
• Adjunct antiemetic for chemotherapy-induced nausea and vomiting and in some ED migraine regimens to reduce recurrence
• Perioperative steroid coverage in chronic steroid users (often used when longer effect is desired or per institutional preference)

Available Forms:

• Injectable solution: commonly 4 mg/mL or 10 mg/mL vials or prefilled syringes for IV/IM use
• Oral tablets: 0.5 mg, 0.75 mg, 1 mg, 1.5 mg, 2 mg, 4 mg, 6 mg (varies by manufacturer)
• Oral solution: e.g., 0.5–1 mg/mL concentrations (check local formularies)
• Specialty formulations (e.g., intra-articular, ophthalmic implants) exist but are less relevant to ED/ICU bedside use

Adult Dosing (Systemic):

Additional Dosing Notes:

• For cerebral edema, higher initial doses (e.g., 10–20 mg IV) and q6h regimens may be used in severe cases; once symptoms stabilize, taper as quickly as clinically feasible to limit complications
• In ARDS/COVID regimens, fixed daily dosing (e.g., 6 mg) is common; avoid abrupt discontinuation after prolonged high-dose steroids—taper may be needed in long courses
• In chronic steroid users, consider total glucocorticoid exposure from all sources; dexamethasone is quite potent, so small doses can be equivalent to large prednisone/hydrocortisone doses

Absolute/Major Contraindications:

• Serious hypersensitivity reaction to dexamethasone or formulation components
• Systemic fungal infections when used as monotherapy without appropriate antifungal coverage

Major Precautions:

• Active infection or sepsis: steroids may mask fever and leukocytosis; use when there is a clear indication and follow sepsis guidelines
• Poorly controlled diabetes or DKA/HHS risk: dexamethasone can significantly increase blood glucose; insulin often needs escalation
• History of peptic ulcer disease or GI bleeding: steroids increase risk when combined with NSAIDs, antiplatelets, or anticoagulants; consider GI prophylaxis
• Psychiatric history (e.g., bipolar disorder, psychosis): steroids can worsen mood instability and precipitate steroid psychosis
• Osteoporosis, myopathy, or frailty: prolonged high-dose therapy increases risk of fractures and ICU-acquired weakness
• Chronic use (>2–3 weeks) at moderate–high doses leads to HPA-axis suppression; abrupt discontinuation may precipitate adrenal crisis

Common (Short- to Moderate-Term):

• Hyperglycemia and increased insulin requirements
• Leukocytosis (neutrophil demargination), which can confuse sepsis workup
• Insomnia, agitation, and mood changes
• Mild fluid retention and hypertension (less than with hydrocortisone)
• Gastric irritation, dyspepsia

Serious / Long-Term:

• Steroid psychosis, severe mood disturbance, suicidality
• GI bleeding or perforation, especially with NSAIDs or severe stress gastritis
• Opportunistic infections and reactivation of latent infections (e.g., TB, strongyloides)
• Myopathy and ICU-acquired weakness, especially when combined with neuromuscular blockade
• Osteoporosis, osteonecrosis (e.g., femoral head) with chronic use
• Adrenal suppression with risk of adrenal crisis upon sudden withdrawal

Elderly Patients:

• Higher risk of adverse effects including hyperglycemia, confusion, and myopathy
• Consider lower doses and closer monitoring

Renal Impairment:

• No specific dose adjustment required, but monitor for fluid retention and electrolyte disturbances

Hepatic Impairment:

• Use with caution; metabolism is hepatic, but no specific dosing guidelines exist

Pregnancy:

• Category C: Crosses placenta; use only if benefit justifies potential fetal risk
• May increase risk of cleft palate with first-trimester use
• Monitor for maternal hyperglycemia and adrenal suppression in neonate

Lactation:

• Enters breast milk; high doses may suppress infant growth and interfere with endogenous corticosteroid production
• Consider risk-benefit for breastfeeding during therapy

Clinical Monitoring:

• Blood glucose trends and insulin requirements, especially in diabetics and critically ill patients
• Vital signs and infection markers (fever pattern, WBC, cultures) to detect masked or worsening infection
• Mental status for delirium, agitation, or steroid psychosis
• Electrolytes and fluid balance in patients with heart failure, renal disease, or on high-dose/prolonged therapy

Long-Term Monitoring:

• In prolonged courses, assess for proximal muscle weakness
• Consider adrenal suppression testing if tapering after long exposure

• 1. Lexicomp. (2024). Dexamethasone: Drug information. Wolters Kluwer.
• 2. The RECOVERY Collaborative Group. (2021). Dexamethasone in hospitalized patients with Covid-19. New England Journal of Medicine, 384(8), 693–704. https://doi.org/10.1056/NEJMoa2021436
• 3. Farkas, J. (2023). Steroids in the ICU. EMCrit Project / IBCC. https://emcrit.org/ibcc/steroids/
• 4. Keh, D., Trips, E., Marx, G., et al. (2016). Effect of hydrocortisone on development of shock among patients with severe sepsis: The HYPRESS randomized clinical trial. JAMA, 316(17), 1775–1785. https://doi.org/10.1001/jama.2016.14799
• 5. Roberts, R. J., Welch, E. K., Devlin, J. W., et al. (2017). Corticosteroids for sepsis and septic shock. Cochrane Database of Systematic Reviews, 12, CD002243. https://doi.org/10.1002/14651858.CD002243.pub3