Dexamethasone Intramuscular Dosing
Intramuscular dexamethasone dosing ranges from 0.5 to 9 mg/day for most indications, with the parenteral dose typically being one-third to one-half of the oral dose given every 12 hours, though specific clinical scenarios require substantially different dosing strategies. 1
General IM Dosing Principles
The FDA-approved initial IM dosage ranges from 0.5 mg/day to 9 mg/day depending on the disease being treated, with less severe conditions requiring lower doses and more severe conditions potentially requiring higher initial doses. 1
The parenteral (IM or IV) dosage is usually one-third to one-half the oral dose, administered every 12 hours. 1
In overwhelming, acute, life-threatening situations, doses exceeding usual dosages may be justified and can be multiples of oral dosages. 1
Indication-Specific IM Dosing
Cerebral Edema
For cerebral edema in adults, give an initial IV dose of 10 mg followed by 4 mg IM every 6 hours until maximum response is achieved. 1
This regimen may be continued for several days postoperatively in patients requiring brain surgery. 1
Transition to oral dexamethasone 1-3 mg three times daily as soon as possible, then taper over 5-7 days. 1
Unresponsive Shock
- High pharmacologic doses are recommended, with regimens ranging from 1-6 mg/kg as a single IV injection to 40 mg initially followed by repeat IV injection every 2-6 hours while shock persists. 1
Pediatric Dosing
- The smallest effective dose should be used in children, preferably orally, approximating 0.2 mg/kg/24 hours in divided doses. 1
Intra-articular and Soft Tissue IM Injections
For large joints: 2-4 mg per injection 1
For small joints: 0.8-1 mg per injection 1
For soft tissue and bursal injections: 2-4 mg 1
For ganglia: 1-2 mg 1
For tendon sheaths: 0.4-1 mg 1
Injection frequency typically ranges from once every 3-5 days to once every 2-3 weeks. 1
Frequent intra-articular injection may cause joint tissue damage. 1
Important Clinical Considerations
Route Equivalency
Dexamethasone has 1:1 bioequivalence between oral, IV, and IM routes—8 mg IM equals 8 mg oral equals 8 mg IV. 2, 3
This equivalency allows flexible route selection based on patient ability to take oral medications without dose adjustment. 2, 3
Dosing Adjustments
Dosage requirements must be individualized based on the disease being treated and patient response. 1
After favorable response, decrease the initial dose in small increments at appropriate intervals until reaching the lowest dose that maintains adequate clinical response. 1
Constant monitoring is needed for changes in clinical status, disease exacerbations/remissions, individual drug responsiveness, and exposure to stressful situations. 1
Discontinuation
- If stopping after long-term therapy, withdraw gradually rather than abruptly to avoid adrenal insufficiency. 1
Common Pitfalls to Avoid
Do not attempt injection into intervertebral joints at any time. 1
Hip joint injection cannot be recommended as an office procedure. 1
Intrasynovial and soft tissue injections should only be employed when affected areas are limited to 1-2 sites. 1
Always inspect parenteral drug products visually for particulate matter and discoloration prior to administration. 1
Do not confuse dexamethasone with other corticosteroids that may have different oral-to-parenteral conversion ratios. 2