No abstract

Background: Despite the widespread use of dose administration aids (DAAs) there is little available data on the stability of drugs during repackaging or storage in these devices. Aim: To investigate the physicochemical stability of paracetamol tablets repackaged in DAAs. Method: Physicochemical stability studies were performed on a commonly used paracetamol tablet directly after heat-sealing in a DAA frequently employed in practice, then at ambient (25 ºC; 60% relative humidity) and accelerated (40 ºC; 75% relative humidity) conditions, over a 3-month period. Physical characteristics of the tablets (weight uniformity, physical appearance, thickness, hardness, friability, disintegration, dissolution rates) were evaluated at time = 0, directly after heatsealing, 1 month and 3 months. Chemical stability was confirmed by high performance liquid chromatography (HPLC). The results were compared to control samples stored in the original packaging at the various environmental conditions studied. Results: All compendial requirements for physicochemical stability were met for both ambient and accelerated conditions over the 3-month period. Chemical stability of paracetamol content fell within the required range of 95-105% of the labelled amount, for all environmental conditions. Conclusion: This study provides evidence on the stability of paracetamol tablets in a DAA, to support pharmacists in making sound clinical and operational decisions regarding the repackaging of paracetamol in these devices. J Pharm Pract Res 2006; 36: 25-8.

Objectives Since sodium valproate, a commonly used antiepileptic drug, has been reported to be unstable in the presence of moisture, our objective was to investigate the effect of repackaging into dose administration aids. Methods Sodium valproate 100 mg immediate-release tablets were repackaged and stored for 56 days at accelerated conditions (40°C/75% relative humidity), room temperature (25°C) and under refrigeration (2-8°C). Samples were analysed at 3, 7, 10, 14, 21, 35, 49 and 56 days to determine chemical stability using high-performance liquid chromatography, while physical testing included assessment of weight changes and dissolution behaviour. Key findings The results revealed that the sodium valproate content in the tablets remained within the acceptable range of 90-110% under all storage conditions for 56 days. Physical stability, however, was not maintained, with a total weight gain of 12.36% under accelerated conditions over the 56 days. Samples stored under all conditions showed variable dissolution compared to the controls, with the amount of sodium valproate in solution following 45 min of dissolution testing below 75% for half of all the intervals determined. Conclusions Repackaging sodium valproate tablets into dose administration aids results in unacceptable weight variation and changes in the dissolution profiles.

Background: Repackaging tablets into a dose administration aid (DAA) requires that the pharmacist consider the stability of the active pharmaceutical ingredient and the excipients of the drug product. Frusemide is susceptible to photodegradation and is commonly repackaged into DAAs. Aim: To evaluate the stability (chemical and physical) of frusemide tablets repackaged into DAAs. Method: Frusemide tablets repackaged into DAAs were evaluated for physicochemical stability over a period of 8 weeks at a controlled room temperature (25 ±2 ºC) and other relevant in-use conditions. In addition, photostability studies were performed according to the International Committee on Harmonisation (ICH) guidelines. Results: Chemical stability was confirmed for all storage conditions, including the ICH light conditions, with the frusemide content within the British Pharmacopoeial range of 95 to 105%. Although the physical stability was confirmed by all tests (weight uniformity, hardness, friability, disintegration, dissolution), storage in a simulated pharmacy environment after one week and exposure to ICH light conditions resulted in a yellow colouration of the tablets. Conclusion: Although the chemical and physical stability of frusemide was within acceptable limits during the study, the discolouration of the tablets from light exposure is unacceptable. It is recommended that DAAs are stored protected from light immediately after repackaging with frusemide tablets, and that patients are counselled to store the DAA in a cool dark place. J Pharm Pract Res 2007; 37: 178-81.

Despite the confirmation of physical and chemical stability within BP limits, the discoloration and the potential for photodegradants to cause adverse effects in patients must lead us to draw the conclusion that the quality of this medication has been compromised. Pharmacists thus need to take this into account in repackaging and storage of prochlorperazine in DAAs and advise patients to store their DAA protected from light, heat and humidity.