US Pharm. 2020;45(12):44-45.

Method of Preparation: Calculate the quantity of each ingredient for the amount to be prepared. Accurately weigh or measure each ingredient. Before compounding, tap the top and bottom of the lidocaine hydrochloride (HCl) bottle. Open the suspension bottle and empty the lidocaine HCl powder into the suspension. Likewise, tap the top and bottom of the diphenhydramine HCl bottle. Remove the cap. Because of the hygroscopic nature and small volume of the powder, use the enclosed spatula to empty the contents into the mouthwash suspension. Close the suspension bottle and vigorously shake it vertically for approximately 20 to 30 seconds. The appropriate quantities of diphenhydramine HCl powder and lidocaine HCl powder have been packaged in each bottle to deliver the required dose of each drug. Residual quantities remaining in the bottles after emptying need not be rinsed out. Package and label.

Use: This preparation is used to ease mucositis symptoms caused by some forms of chemotherapy and radiation therapy, as well as for aphthous ulcers, other oral ulcers, and other mouth pain.

Packaging: Package in the container in which it is provided and compounded.

Labeling: Keep out of reach of children. Avoid contact with the eyes. Keep container tightly closed. Keep refrigerated. Protect from light. Protect from freezing. Shake well before each use. Discard after ____ [time period].

Stability: Based on real-time controlled room temperature and humidity testing, the finished, compounded Mouthwash BLM Compounding product is stable for at least 180 days.1

Quality Control: Quality-control assessment can include weight/volume, pH, specific gravity, active drug assay, color, rheologic properties, physical observation, and physical stability (discoloration, foreign materials, gas formation, and mold growth).2

Discussion: This formula is equivalent to the active ingredients in compounded Magic Mouthwash [Benadryl Elixir:Lidocaine HCl 2% Viscous:
Maalox Suspension (1:1:1 v/v/v)]. The Mouthwash BLM Compounding Kit contains premeasured diphenhydramine HCl powder, lidocaine HCl powder, and mouthwash suspension (aluminum hydroxide, magnesium hydroxide, and simethicone, plus inactive ingredients). The 119-mL size of the compounded preparation contains diphenhydramine HCl 0.1 g, lidocaine HCl 0.8 g, and FIRST Mouthwash Suspension 118 mL.

Diphenhydramine HCl (C17H21NO.HCl, MW 291.82), an H1-receptor antagonist used for the relief of hypersensitivity reactions, occurs as a white, odorless, crystalline powder. It slowly darkens on exposure to light, and its solutions are practically neutral. Diphenhydramine HCl is freely soluble in water and in alcohol. It elicits mild anesthetic properties when used topically.3

Lidocaine HCl (C14H22N2O.HCl.H2O, MW 288.81) occurs as a white, odorless, crystalline powder with a slightly bitter taste. It is an amide-type local anesthetic with a rapid onset and an intermediate duration of action. It is highly soluble in water (1:0.7) and in alcohol (1:1.5).1 A 0.5% aqueous solution has a pH in the range of 4.0 to 5.5, and the injection has a pH in the range of 5.0 to 7.0. Lidocaine HCl should be protected from light.3,4

Aluminum hydroxide [Al(OH)3, MW 78.00] occurs as a white, odorless, tasteless, amorphous powder that is insoluble in water and in alcohol. It is soluble in dilute mineral acids and in solutions of fixed alkali hydroxides. Aluminum hydroxide should be preserved in tight containers.3

Magnesium hydroxide [Mg(OH)2, MW 58.32], which is used as an antacid and laxative, occurs as a bulky white powder. It is soluble in dilute acids and is practically insoluble in water (with a pH of 9.5-10.5) and in alcohol.5

Simethicone {dimethicone, dimethyl silicone fluid, poly(dimethylsiloxane), CH3[Si(CH3)2.O]nSi(CH3)3} is a fluid silicone that occurs as a clear, colorless, odorless liquid that is insoluble in water, alcohol, acetone, and methyl alcohol. It is very slightly soluble in isopropyl alcohol but is soluble in amyl acetate, chlorinated hydrocarbons, ether, n-hexane, petroleum spirit, benzene, toluene, and xylene. Simethicone should be stored in airtight containers. It is water-repellent and has a low surface tension. One use for simethicone is to minimize foaming in products by allowing gas bubbles to merge and be more easily dispelled.6

Inactive ingredients include benzyl alcohol, butylparaben, cherry flavor, D&C Red #28, FD&C Red #40, hydroxyethylcellulose, Magnasweet 185, propylparaben, purified water, saccharin sodium, and sorbitol solution.1


1. FIRST-Mouthwash BLM package insert. Wilmington, MA: Cutis Pharma; September 2016.
2. Allen LV Jr. Standard operating procedure for performing physical quality assessment of oral and topical liquids. IJPC. 1999;3:146-147.
3. U.S. Pharmacopeia/National Formulary [current revision]. Rockville, MD: U.S. Pharmacopeial Convention, Inc; May 2019.
4. McEvoy GK, ed. AHFS Drug Information 2016. Bethesda, MD: American Society of Health-System Pharmacists; 2016:3354-3356.
5. Allen LV Jr, ed. Remington: The Science and Practice of Pharmacy. 22nd ed. London, England: Pharmaceutical Press; 2013:1649.
6. Sweetman SC, ed. Martindale: The Complete Drug Reference. 36th ed. London, England: Pharmaceutical Press; 2009:1770-1771.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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