Avaliação da estabilidade de espironolactona para administração por sonda enteral

Abstract

The administration of medication by feeding tube is a common practice in hospitalized patients. However, some drugs are not available in liquid form, the most suitable for such administration, resulting in manipulation of drugs without appropriate technical criteria. Spironolactone is a synthetic steroid that belongs to the group of potassium sparing used in patients with liver cirrhosis. This drug has a chemical structure with a lactone group susceptible to hydrolysis. Although the susceptibility to hydrolysis of spironolactone and the solubility characteristics, the drug is commonly crushed and / or dispersed in water for administration by feeding tube. The objective of this study was to investigate the stability of the drug spironolactone prepared from tablets by the method of dosing syringes (PORTELA, 2013) for administration by feeding tube. The stability evaluation was made by ultraviolet spectrophotometry (238 nm) according to the method of the British Pharmacopoeia. The specificity, linearity and precision of the method were analyzed in the laboratory. To evaluate the stability of the spironolactone, a tablet of spironolactone 25 mg was introduced in a 10 ml syringe, the volume of which was filled with distilled water. After a set time of 10, 30, 60, 120, 180 and 240 minutes, dilutions were performed with the contents of the syringe, resulting in a theoretical concentration of 10 µg/mL which was submitted to ultraviolet spectrophotometric reading at 238 nm for the calculation of the content. The pharmacopoeial method has been reproduced in the laboratory, with r2 = 0,9968 and equation y = 0,0461x – 0,0135 constructed using the concentration range between 5 and 15 µg/mL. Specificity was evaluated by the non-interference of the tablet excipients at a wavelength of 238 nm. In the stability study of spironolactone, the obtained content in different analysis times obeyed the allowed range between 95-105%. The analysis method was adequate and reproducible. The spironolactone remained stable in the administration proposed condition.