What is the recommended formulation and usage instructions for a magic mouthwash for pain relief?

Magic Mouthwash Formulation and Instructions

The recommended magic mouthwash formulation is equal parts diphenhydramine, antacid (aluminum hydroxide-magnesium hydroxide), and viscous lidocaine in a 1:1:1 ratio. 1

Standard Formulation

• Ingredients (1:1:1 ratio):
  • Diphenhydramine (liquid) - 1 part
  • Aluminum hydroxide-magnesium hydroxide (antacid) - 1 part
  • Viscous lidocaine 2% - 1 part

Prescription Format for Pharmacy

Rx: Magic Mouthwash
    Diphenhydramine liquid + Aluminum hydroxide-magnesium hydroxide + Viscous lidocaine 2%
    Mix in equal parts (1:1:1 ratio)
    Disp: 180-240 mL
    Sig: Swish 5-10 mL in mouth for 1-2 minutes, then spit out. 
         Use every 4-6 hours as needed for oral pain.
         Do not eat or drink for 30 minutes after use.

Patient Instructions

1. Dosage: Swish 5-10 mL (1-2 teaspoons) in mouth
2. Duration: Hold in mouth for 1-2 minutes, then spit out
3. Frequency: Use every 4-6 hours as needed, not more than 3-4 times daily 2
4. Administration: Shake well before using
5. Post-application: Do not eat or drink for at least 30 minutes after use
6. Storage: Store at room temperature in amber container
7. Expiration: Use within 21 days of preparation 3

Clinical Considerations

• Stability: Research shows that magic mouthwash has a beyond-use dating (BUD) of 21 days when stored at room temperature in amber containers 3
• Alternative formulations: Some institutions use different ratios (1:2.5:2.5) or add other ingredients such as nystatin or corticosteroids for specific conditions 4
• Efficacy: While widely used, evidence for efficacy is mixed. Some studies suggest separate administration of components may be more effective 3
• Safety concerns: Patients should be warned about potential numbness that could affect swallowing and increase risk of aspiration

Special Populations

• Children under 12: Consult a physician before use 2
• Cancer patients: Particularly beneficial for management of oral mucositis in patients receiving chemotherapy or radiation therapy 1
• Immunotherapy patients: Recommended for management of oral mucosa inflammation in patients receiving immune checkpoint inhibitors 1

Potential Pitfalls

• Numbness: The lidocaine component can cause numbness that may affect swallowing; patients should avoid eating for 30 minutes after use
• Limited duration: Effects typically last only 15-45 minutes
• Taste: Some patients may find the taste unpleasant; cooling the solution may improve palatability
• Allergies: Confirm patient has no allergies to any components before prescribing

Magic mouthwash is a valuable option for managing oral pain associated with mucositis, stomatitis, and other inflammatory conditions of the oral cavity, with the NCCN specifically recommending it as part of supportive care for patients with oral mucosa inflammation 1.