Mebeverine HCl and aluminium/magnesium antacid interactions: A potential impact on electrolyte replacement therapy

Abstract

When antacids are administered with other drugs, they can alter the absorption, bioavailability, and/or excretion of concomitantly administered drugs. This study aims to characterize the in vitro interaction between different formulations of mebeverine HCl and magnesium trisilicate antacids and salts used for electrolyte-replacement therapy. The dissolution profiles of different formulations of mebeverine alone and in the presence of aluminium/magnesiumcontaining antacids and salts were studied. The release profiles of the drugs and the model and mechanisms of drug release were determined using differential scanning calorimetry and infrared techniques. Polyethylene glycol laxative (Movicol) combined with aluminium/magnesium hydroxide (Rialox, three tablets) [225 mg Al(OH)3, 200 mg Mg(OH)2] resulted in 59.2%, 55.7%, and 30% loss of mebeverine HCl in 135 mg film-coated tablets (Mebagen), 135 mg sugar-coated tablets (Colospasmin forte), and 200 mg retard capsules (Duspatalin), respectively. Three tablets of Rialox, three tablets of Moxal [405 mg Al(OH)3, 100 mg Mg(OH)2], and Movicol resulted in 50.7%, 27.7%, and 35.18% loss, respectively, of mebeverine HCl in Duspatalin capsules. Moxal suspension combined with Movicol led to 41.8% loss of mebeverine HCl in Duspatalin capsules. The loss of mebeverine HCl in each case appeared to be caused by absorption. The calorimetry and infrared results suggest that mebeverine HCl interacts with the antacids and with Movicol. These results should be added to the in vitro drug-drug interaction chart. It is advisable to administer other drugs at least 0.5-1.0 h before antacid ingestion to ensure consistent absorption and effect and to avoid potential interactions.