Stability of partial doses of omeprazole-sodium bicarbonate oral suspension

Omeprazole-sodium bicarbonate powder for oral suspension has recently been marketed. The manufacturer provides no information regarding the acceptability of using partial doses and recommends that the reconstituted suspension be administered immediately after preparation.

To determine the stability of the powder for oral suspension over 45 days, evaluate the stability of a partial dose (<20 mg) following exposure to Simulated Gastric Fluid USP (SGF) over 2 hours, and determine the feasibility of administering the suspension through neonatal and pediatric nasogastric feeding tubes compared with lansoprazole.

Three identical samples of omeprazole-sodium bicarbonate suspension 2 mg/mL were stored in the refrigerator (3-5 degrees C) and assayed by high-performance liquid chromatography immediately after preparation and at 7, 15, 30, and 45 days. Stability of a 1 mg/kg dose with an estimated volume of SGF for a simulated 12.7 kg pediatric patient was determined in triplicate over 2 hours at 37 degrees C. The ability to administer a typical dose of omeprazole suspension and lansoprazole suspension (microgranules and water compounded from lansoprazole oral disintegrating tablets) was assessed in triplicate using 3 different sizes of neonatal/pediatric nasogastric feeding tubes.

At least 98% of the initial concentration of omeprazole remained throughout the 45 day study period in all suspensions. The suspension maintained at least 93% of the initial concentration following exposure to SGF for 2 hours. The lansoprazole bead mixture partially clogged the 6 French feeding tube and completely clogged the 5 French feeding tube. The omeprazole-sodium bicarbonate suspension was easily administered through all 3 sizes of neonatal/pediatric feeding tubes.

Omeprazole-sodium bicarbonate suspension 2 mg/mL prepared from 20 mg packets was stable for at least 45 days when stored at 3-5 degrees C. A partial dose of 12.7 mg was stable following exposure to SGF for 2 hours at 37 degrees C. This suspension can be easily administered through 5, 6, and 8 French neonatal/pediatric feeding tubes and, when taking time and ease of preparation into account, it is cost competitive with simple omeprazole suspension.