Abstract
The stability of cefditoren in three kinds of oral liquid preparations at 4 and $25^{\circ}C$ was studied for 90 days. Two tablets of 100 mg cefditoren pivoxil were mixed with 200 mL of each oral liquid syrup, which is Pebron syrup (oxolamine citrate 10 mg/mL), $Mucopect^{(R)}$ syrup (ambroxol hydrochloride 3 mg/mL) or $Tyrenol^{(R)}$ suspension (acetaminophen encapsulated 32 mg/mL). Three samples of each formulation were refrigerated $(4^{\circ}C)$ and three were stored at room temperature $(25^{\circ}C)$. At predetermined time, samples were assayed by stability-indicating HPLC method. The chromatographic analysis after deliberate degradation showed no evidence of any breakdown product likely to interfere with the chromatographic peak of the parent substance. The relation between cefditoren pivoxil concentration and peak area was linear from 10 to $150{\mu}g/mL\;(r^2=0.9998)$. The analysis method was precise, with coefficients of variation no greater than 3.6%. Cefditoren was stable in $Mucopect^{(R)}$ syrup up to 4 weeks regardless of the temperature; in $Tyrenol^{(R)}$ suspension and Pebron syrup, it was stable for at least 28 and 45 days, and 7 and 45 days at 25 and $4^{\circ}C$, respectively. The percentages of initial cefditoren concentration remaining after 90 days were $51.5{\pm}1.8\;and\;80.9{\pm}5.6%,\;61.7{\pm}7.8\;and\;70.2{\pm}7.3%,\;and\;39.9{\pm}3.2\;and\;81.4{\pm}5.5%$ in $Mucopect^{(R)}$ syrup, $Tyrenol^{(R)}$ suspension and $Pebron^{(R)}$ syrup at 25 and $4^{\circ}C$, respectively. The pH variations of all test solutions were minimal, which was within 0.5. The results indicated that the stability of cefditoren was significantly affected by liquid solutions mixed with cefditoren, and storage tempertature.
(Graduate School of Clinical Health Sciences, Ewha Womans University)