Is a 1 mg/mL oral dexamethasone solution commercially available?

Dexamethasone 1 mg/mL Oral Solution Availability

Yes, a 1 mg/mL oral dexamethasone solution is available through extemporaneous compounding, and the injectable formulation can be administered orally as a common alternative practice. 1, 2

Commercially Available Options

Extemporaneously Compounded Solutions

• Compounded 1 mg/mL suspensions can be prepared using commercially available vehicles (Oral Mix and Oral Mix SF) and remain stable for up to 91 days when stored in amber glass or plastic bottles at either room temperature (25°C) or refrigerated (4°C). 1
• These compounded suspensions maintain at least 96% of the original dexamethasone concentration throughout the 91-day storage period with no notable changes in color, taste, odor, or pH. 1
• Plastic oral syringes can also be used for storage at room temperature with equivalent stability. 1

Injectable Formulation Used Orally

• Dexamethasone sodium phosphate for injection (DSPI) is routinely administered orally in emergency departments nationwide, particularly for pediatric asthma and croup, despite this being an off-label route of administration. 2
• The relative bioavailability of DSPI when given orally is approximately 87-91% compared to commercial oral concentrate formulations, with an absolute bioavailability of 75.9%. 2
• While DSPI does not meet strict bioequivalence criteria when compared to dexamethasone oral concentrate (90% CI for AUC was 78.8%-96.9%, falling slightly below the 80% lower bound), existing clinical literature supports its efficacy despite this pharmacokinetic difference. 2

Clinical Implications

Dosing Considerations

• No dose adjustment is required when converting between IV and oral dexamethasone formulations, as they have equivalent 1:1 dosing. 3
• For example, 8 mg IV dexamethasone equals 8 mg oral dexamethasone across all clinical applications including antiemetic regimens. 3
• Major oncology guidelines (ASCO, NCCN) consistently list identical doses for both oral and IV routes, confirming interchangeable dosing in clinical practice. 3

Common Pitfalls to Avoid

• Do not confuse dexamethasone with other corticosteroids (such as prednisone or methylprednisolone) that have different oral-to-IV conversion ratios. 3
• When using DSPI orally, be aware that the slightly lower bioavailability (87-91%) has not required dose adjustments in clinical practice, as efficacy data support current dosing protocols. 2
• For low-dose products (0.1 mg/mL formulations), solid-phase extraction methods may be needed for quality control testing due to the high ratio of excipients to active drug. 4

Practical Applications

• For antiemetic therapy: ASCO guidelines specify dexamethasone can be given "once daily (either orally or intravenously)" without dose adjustment for chemotherapy-induced nausea. 3
• For pediatric use: Liquid formulations are particularly suitable because they facilitate exact dosing and proper intake compared to tablets. 5
• Bioequivalence data: Commercial liquid oral dexamethasone formulations (when available) demonstrate bioequivalence to tablet formulations, with 90% CIs for AUC and Cmax falling within the 80-125% acceptance range. 5