Stability of furosemide and torasemide in parenteral nutrition admixture

Furosemide and torasemide (loop diuretics) are used to treat hypertension or pulmonary edema. They are often administered in the parenteral route. In critically ill patients, there is a problem of a limited number of venous accesses, which complicates the polytherapy. Drugs of unknown compatibility must be administered separately, and the problem increases in patients receiving parenteral nutrition. Lipid emulsions have been introduced into clinical practice as a high-calorie, non-glucose source of energy for parenteral administration, but they can also be used as lipophilic drug carriers. In this paper, the parenteral nutrition admixture (PNA) Nutriflex Lipid special was used as a drug carrier for furosemide and torasemide. For this purpose, drug stability tests (HPLC method) were carried out in various light and temperature conditions, imitating clinical conditions, and the parameters of the lipid emulsion (pH, zeta potential, the size of the emulsion droplets and polpolydispersity) were tested. Furosemide and torasemide added to Nutriflex Lipid special did not cause significant changes in the physicochemical properties of PNA. Changes in pH and MDD were within acceptable limits. Both drugs when added to Nutriflex Lipid special were degraded, dependent on the storage conditions and the chemical structure.