From the FDA Drug Label
Adult: ... For symptomatic treatment of irritated or inflamed mucous membranes of the mouth and pharynx, the usual adult dose is one 15 mL tablespoonful undiluted. ... This dose should not be administered at intervals of less than three hours, and not more than eight doses should be given in a 24-hour period. Pediatric: ... For children over 3 years of age ... the dose of lidocaine hydrochloride should not exceed 75-100 mg (3. 7 to 5 mL of Lidocaine Hydrochloride Oral Topical Solution, USP (Viscous) 2%). ... For infants and in children under 3 years of age, the solution should be accurately measured and no more than 1. 2 mL be applied to the immediate area with a cotton-tipped applicator. Wait at least 3 hours before giving the next dose; a maximum of four doses may be given in a 12-hour period.
The recommended dosing for magic mouthwash (lidocaine hydrochloride oral topical solution) is:
- Adults: 15 mL undiluted, not more than 8 doses in 24 hours, and at least 3 hours between doses.
- Children over 3 years: up to 75-100 mg (3.7 to 5 mL), at least 3 hours between doses.
- Children under 3 years: no more than 1.2 mL, at least 3 hours between doses, and a maximum of 4 doses in 12 hours 1.
From the Research
Magic mouthwash should be dosed as 5-10 mL swished in the mouth for 1-2 minutes, then either spit out or swallowed, depending on the formulation, and repeated every 4-6 hours as needed for oral pain and inflammation, as supported by the most recent and highest quality study 2. The standard formulation often contains equal parts of diphenhydramine (Benadryl), viscous lidocaine, and an antacid like Maalox or Mylanta, though compositions vary widely. Some formulations may include antibiotics (nystatin), corticosteroids (dexamethasone), or other medications depending on the specific condition being treated. Before using, shake the bottle well to mix all ingredients properly. Patients should avoid eating or drinking for 30 minutes after use to maximize effectiveness. Magic mouthwash works by combining multiple mechanisms: the antihistamine reduces inflammation, lidocaine provides local anesthesia, and antacids coat and protect irritated tissues. For severe mucositis or stomatitis, treatment typically continues for 7-14 days or until symptoms resolve. If symptoms worsen or don't improve within 7 days, patients should contact their healthcare provider for reevaluation. Key points to consider when prescribing magic mouthwash include:
- The use of doxepin mouthwash or diphenhydramine-lidocaine-antacid mouthwash vs placebo significantly reduced oral mucositis pain during the first 4 hours after administration, as shown in the study 2.
- Topical treatments alleviate and prevent oral mucositis, and can assist maintain oral balance and moistness by modulating oral bacteria and replacing saliva, as discussed in the review 3.
- A beyond-use dating (BUD) of 21 days is recommended for lidocaine prepared with diphenhydramine and aluminum hydroxide-magnesium hydroxide-simethicone in ratios of 1:1:1 and 1:2.5:2.5 and stored at room temperature in amber oral plastic syringes, as determined in the study 4.