Omeprazole 1 mg/mL or 2 mg/mL Oral Suspension

US Pharm. 2018;43(12):47-48.

Method of Preparation: Calculate the needed quantity of each ingredient. Accurately weigh or measure each ingredient. Place the sodium bicarbonate in a suitable container, add about 50 mL of purified water, and mix well. Add the omeprazole, followed by sufficient additional purified water, to final volume and mix well. Package and label.

Use: Omeprazole oral suspension has been used to treat gastrointestinal problems, especially gastroesophageal reflux disease (GERD) in pediatric patients and newborns.

Packaging: Package in tight, light-resistant containers.

Labeling: Keep out of reach of children. Keep refrigerated. Shake well. Discard after ____ [time period].

Stability: A beyond-use date of up to 45 days stored in a refrigerator (controlled cold temperature) may be used for the official USP 2-mg/mL preparation. For the 1-mg/mL preparation, since there are no reported stability studies, the USP default beyond-use date of 14 days’ refrigeration may be used.¹

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

Discussion: Omeprazole is a proton pump inhibitor that is used to treat gastrointestinal problems, especially GERD, which is common in pediatric patients and also occurs in newborns. The concentration and composition of this preparation can be easily modified to accommodate patient requirements when a patient is intolerant to an ingredient in the manufactured products. The preparation may be administered after being mixed with a suitable liquid or via nasogastric tube. The critical factor is to maintain the high pH of the preparation.

Omeprazole (Prilosec, C₁₇H₁₉N₃O₃S, MW 345.42) occurs as a white to off-white powder that melts with decomposition at about 155°C. It is soluble in water 1 g in 8,000 mL. Omeprazole’s degradation rate increases with decreasing acidic pH values, but the drug has acceptable stability under alkaline conditions. Omeprazole Oral Suspension USP at a concentration of 2 mg/mL is an official USP compounded preparation.^1,3

Examples of commercial liquid products that may or may not be suitable for patients are as follows:

Prilosec for Delayed-Release Oral Suspension—Each packet contains either 2.8 mg or 11.2 mg of omeprazole magnesium (equivalent to 2.5 mg or 10 mg of omeprazole) in the form of enteric-coated granules with the following inactive ingredients: glyceryl monostearate; hydroxypropyl cellulose; hypromellose; magnesium stearate; methacrylic acid copolymer C; polysorbate; sugar spheres; talc; triethyl citrate; and inactive granules that are composed of citric acid, crospovidone, dextrose, hydroxypropyl cellulose, iron oxide, and xanthan gum. The omeprazole granules and inactive granules are constituted with water to form a suspension and are given by oral, nasogastric, or direct gastric administration.⁴

FIRST-Omeprazole Compounding Kit—This product consists of omeprazole powder and FIRST-PPI Suspension, which contains artificial strawberry flavor, benzyl alcohol, FD&C Red #40, Magnasweet 100, poloxamer 188, propylene glycol, purified water, simethicone emulsion, sodium bicarbonate, sodium citrate (dihydrate), sucralose, and xanthan gum. When compounded, the final product provides 2 mg per mL of omeprazole in FIRST-PPI Suspension.⁵

Sodium bicarbonate (baking soda, sal de Vichy, NaHCO₃, MW 84.01) occurs as a white, crystalline powder that is stable in dry air, but it slowly decomposes in moist air. It is soluble 1 g in 12 mL water, and its freshly prepared solutions are alkaline to litmus; a pH of 8.3 is typical for a freshly prepared 0.1 M aqueous solution at 25°C. Sodium bicarbonate should be preserved in well-closed containers. Sodium Bicarbonate Injection USP has a pH of 7.0 to 8.5.^1,6

Purified water is water that is obtained by distillation, ion exchange, reverse osmosis, or some other suitable process. It is miscible with most polar solvents and is chemically stable in all physical states.⁷

REFERENCES

1. U.S. Pharmacopeia/National Formulary [current revision]. Rockville, MD: U.S. Pharmacopeial Convention, Inc; November 2018.
2. Allen LV Jr. Standard operating procedure for performing physical quality assessment of oral and topical liquids. IJPC. 1999;3:146-147.
3. Allen LV Jr, ed. Remington: The Science and Practice of Pharmacy. 22nd ed. London, England: Pharmaceutical Press; 2013:1634-1635.
4. Prilosec. www.rxlist.com/prilosec-drug.htm. Accessed November 8, 2018.
5. FIRST-PPI Suspension (omeprazole) package insert. Wilmington, MA: CutisPharma; October 2016.
6. Quinn ME. Sodium bicarbonate. In: Sheskey PJ, Cook WG, Cable CG, eds. Handbook of Pharmaceutical Excipients. 8th ed. Washington, DC: American Pharmaceutical Association; 2017:846-850.
7. Dubash D, Shah U. Water. In: Sheskey PJ, Cook WG, Cable CG, eds. Handbook of Pharmaceutical Excipients. 8th ed. Washington, DC: American Pharmaceutical Association; 2017:1012-1016.

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