Section 14 · Monograph
Dexamethasone
Reviewed Nov 2026FDA label
DecadronCorticosteroid
- Forms
- Tab: 0.5, 0.75, 1, 1.5, 2, 4, 6mg | IV: 4, 10mg/mL
- Dose
- Vasogenic edema: 10mg IV load, then 4mg q6h (range 4-16mg/day divided)
- MOA
- Reduces vasogenic edema and inflammation
Indications
- Cerebral edema associated with primary or metastatic brain tumor, craniotomy or head injuryFDA-labeled
- Broad anti-inflammatory and immunosuppressive uses (endocrine, rheumatic, allergic, respiratory, and other conditions)FDA-labeled
Off-Label Uses
- Spinal cord compression from metastatic diseaseOff-label
- Transitional therapy for cluster headacheOff-label
- Antiemetic in chemotherapyOff-label
Mechanism of Action
- Potent long-acting glucocorticoid that reduces vascular permeability and inflammatory mediators, decreasing vasogenic edema around tumors
Full Dosing
Adult / usual
- Vasogenic edema: 10mg IV loading dose, then 4mg every 6 hours (range 4-16mg/day divided); taper as clinically possible
- Add GI prophylaxis and glucose monitoring with prolonged courses
- Avoid abrupt withdrawal after prolonged use (adrenal suppression)
Contraindications
- Systemic fungal infections
- Known hypersensitivity
- Live vaccines during immunosuppressive dosing
Drug Interactions
- CYP3A4 inducers (carbamazepine, phenytoin, phenobarbital) lower dexamethasone levels
- Dexamethasone induces CYP3A4 and may lower levels of many co-administered drugs
- NSAIDs increase GI ulcer risk
- May alter anticoagulant response
Adverse Effects
- Hyperglycemia
- Insomnia, mood change, psychosis
- GI bleeding and ulcer, especially with NSAIDs
- Proximal steroid myopathy
- Increased infection risk (consider PJP prophylaxis with prolonged courses)
- Adrenal suppression, osteoporosis
Monitoring Parameters
- Blood glucose
- Blood pressure and electrolytes
- Mood and sleep
- Consider PJP and GI prophylaxis and bone health on long courses
Pregnancy & Lactation
- Corticosteroids cross the placenta (used for fetal lung maturity); weigh risks and benefits
- Small amounts excreted in milk