When lansoprazole orally dispersing tablets (30 mg) are administered through a tube, a residue often remains in the syringe and tube because the tablets contain fine enteric granules which are nearly insoluble in water. As a solution, we added thickening agents and examined their effectiveness in reducing the residue in syringes.
The amount of lansoprazole residue in syringes was 11.4±1.3 mg when the agents were not added (Group A) and 1.3±0.6 mg when the agents were added (Group B). For Group A, the residue from a single injection was approximately 30-40% of the total amount of lansoprazole, while there was almost no lansoprazole residue for Group B. Performed by nurses, tube administration took slightly longer for Group B - 51.4±5.5 sec for Group A and 70.8±6.1 sec for Group B.
Our solution of just adding thickening agents improved the dispersivity of the drug in the suspension as well as the mobility of the drug suspension, by getting the particles and solvent traveling at the same speed. It enabled injection to be performed smoothly and decreased the amount of residue in the syringe. The addition of thickening agents is therefore useful in tube administration because avoiding any lansoprazole loss would help ensure that the expected efficacy is achieved, since this is dosedependent.
