How to Order Magic Mouthwash
Order magic mouthwash as equal parts diphenhydramine 12.5 mg/5 mL elixir, viscous lidocaine 2%, and aluminum hydroxide-magnesium hydroxide antacid, dispensed in 15 mL doses to be used four times daily (swish and spit), with a beyond-use date of 21 days when stored at room temperature. 1, 2
Standard Formulation and Prescription
The most commonly used magic mouthwash formulation consists of three core ingredients in equal proportions 3:
- Diphenhydramine 12.5 mg/5 mL oral solution (available as liquid elixir) 4
- Viscous lidocaine 2% (topical anesthetic)
- Aluminum hydroxide-magnesium hydroxide antacid (Maalox or equivalent)
Specific Prescription Format
Write the prescription as:
- Diphenhydramine 12.5 mg/5 mL elixir: 150 mL
- Lidocaine viscous 2%: 150 mL
- Aluminum hydroxide-magnesium hydroxide antacid: 150 mL
- Mix equal parts; dispense 450 mL total
- Sig: Swish 15 mL in mouth for 1-2 minutes and spit out, four times daily before meals and at bedtime
- Beyond-use date: 21 days from compounding 2
Dosing Instructions
Administer 15 mL four times daily (QDS), particularly before meals and at bedtime 5, 1. The NCCN guidelines specifically recommend this formulation as "equal parts diphenhydramine, antacid, and viscous lidocaine" 1.
Most institutions use either every 4 hours (36%) or every 6 hours (36%) dosing schedules 3. The four-times-daily regimen aligns with guideline recommendations for mucositis management 5.
Critical Stability and Storage Considerations
Important caveat: Research demonstrates that magic mouthwash containing lidocaine, diphenhydramine, and antacid has a beyond-use date of only 21 days when stored at room temperature in amber oral syringes 2. This is significantly shorter than many practitioners assume.
Alternative approach for extended stability: Consider dispensing lidocaine separately from the other ingredients, as lidocaine alone has a 90-day beyond-use date 2. This allows:
- Lidocaine packaged separately with 90-day stability
- Diphenhydramine and antacid mixed together
- Patient combines immediately before use
Alternative Formulations
While the 1:1:1 ratio is standard, some institutions use a 1:2.5:2.5 ratio (less diphenhydramine, more lidocaine and antacid), though stability remains 21 days for both formulations 2.
Optional addition: Nystatin suspension 1 mL (100,000 units) four times daily can be added if oral candidiasis is present or suspected 5, 6. However, check for drug interactions with any concurrent medications 5.
Patient Instructions
Provide clear instructions:
- Swish and spit (do not swallow) 2
- Use before meals to maximize comfort during eating 5, 1
- Avoid eating or drinking for 30 minutes after use
- Store at room temperature in amber container
- Discard after 21 days 2
Adjunctive Measures
Magic mouthwash should be part of comprehensive oral care 1:
- Good oral hygiene: Twice-daily gentle toothbrushing with soft bristles 5
- Saline rinses: 10 mL four times daily (1 teaspoon salt in 500 mL water) 5
- Dietary modifications: Avoid crunchy, spicy, acidic, or hot foods/beverages 5, 1
- Adequate hydration: Maintain 1.5 L/day fluid intake 5
- Avoid alcohol-based mouthwashes 5
Evidence Limitations
Critical consideration: While magic mouthwash is widely used, recent high-quality evidence shows limited clinical benefit. A 2019 randomized trial found that diphenhydramine-lidocaine-antacid mouthwash reduced mucositis pain by only 3.0 points more than placebo (95% CI 0.1-5.9), which was less than the minimal clinically important difference of 3.5 points 7. The effect was statistically significant but clinically marginal.
Despite this, magic mouthwash remains recommended in current NCCN guidelines for symptomatic relief of oral mucositis 1, and the formulation is standardized across multiple international consensus guidelines 5.
When to Consider Alternatives
If magic mouthwash provides inadequate relief: