Compounding and stability evaluation of atorvastatin extemporaneous oral suspension using tablets or pure powder

Background

Statins are the first-line therapy for lowering high lipid levels. Atorvastatin calcium (AtC) is the most commonly prescribed statin. It inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase which converts HMG-CoA into mevalonic acid, a cholesterol precursor.

Objective

To compound and evaluate the stability of AtC suspension (0.4% w/v) using commercial tablets or pure AtC powder as the source of the active pharmaceutical ingredient.

Method

Several AtC suspension formulations were produced using commercial AtC tablets or AtC pure powder as the source of the active ingredient. The most suitable one in terms of general organoleptic properties and dissolution was selected for stability studies. For this purpose, samples of final suspensions were stored at room temperature and in the refrigerator. Assay, pH, organoleptic properties and microbial contamination were evaluated according to the USP specifications. High performance liquid chromatography was used for the analysis and quantification of AtC in the studied samples.

Results

The obtained suspension (S4) had good organoleptic properties. It showed complete dissolution of AtC within 30 min. However, the suspension prepared from crushed tablet (S_t4) showed a better dissolution profile than that prepared from pure powder (S_p4). The prepared formula had unchanged pH, which remained around 9.9. S_t and S_p formulas were both free from microbial contamination. Both products showed good stability within at least the period of use of the 100 mL AtC bottles.

Conclusions

AtC extemporaneous suspension was successfully prepared using tablets as a source of AtC or pure AtC powder. However, S_t4 had a better dissolution profile than S_p4. This study provides a solution for patients with swallowing difficulties or feeding tubes who are unable to take medicines in solid oral dosage forms. Community pharmacists can prepare the suspension using AtC tablets as the source of the active ingredient.

Compatibility of proton pump inhibitors in a preservative-free suspending vehicle

Objectives

To evaluate the microbiological and physicochemical compatibility of commonly used proton pump inhibitors (PPIs) esomeprazole, lansoprazole, omeprazole and pantoprazole compounded at a single concentration using SyrSpend SF Alka and stored at refrigerated temperatures (omeprazole was also stored at room temperature because it has the most widespread use).

Methods

Compatibility was assessed by measuring the per cent recovery at varying time points throughout a 90-day period. Quantification of the APIs was performed by a validated high performance liquid chromatography (HPLC-UV) method. This same assay was also used to determine the dosage content uniformity of the suspensions. Microbiological stability ('test in use') was assessed during 60 days and total aerobic microbial count (TAMC), total combined yeasts and moulds count (TYMC), detection of Escherichia coli and pH determination were performed. Antimicrobial effectiveness testing was determined following European Pharmacopoeia guidelines.

Results

Beyond-use dates of maximum 60 days for omeprazole (5 mg/mL), pantoprazole (3 mg/mL) and esomeprazole (3 mg/mL) were established. All suspensions that met the physicochemical criteria for stability also met the content uniformity criteria. The suspensions showed no antimicrobial efficiency against bacteria, yeasts and moulds as SyrSpend SF Alka is an unpreserved vehicle, but the 'test in use' showed that the suspensions can remain microbiologically stable for up to 60 days.

Conclusions

SyrSpend SF Alka can be used to compound palatable (taste-masking properties) preservative-free oral suspensions with almost all commonly used PPIs.

Effects of implementing a clinical pharmacist service in a mixed Norwegian ICU

Objectives

An unacceptably high proportion of patients admitted to intensive care units (ICUs) develop drug-related problems (DRPs). DRPs might cause harm and increase costs and length of stay. The implementation of a clinical pharmacist service has been shown to detect a high number of DRPs and contributes effectively to solving these across different healthcare systems. However, this has not been prospectively studied in a mixed tertiary Norwegian ICU.

Methods

During a 12-month period from October 2012, a clinical pharmacist was dedicated to review medications 3 h daily (Monday to Friday). DRPs were reported at the ICU conference and included advice by the pharmacist for each case. All DRPs were categorised and the clinical impact was documented for later analysis. Drug-related questions from the staff were categorised and answered.

Results

363 of 549 patients admitted to the ICU received medication reviews. 641 DRPs were detected in 194 of these patients (mean 1.8 DRPs per patient, range 0-25). Too high a dose, significant drug interactions and unnecessary or inappropriate drugs were among the most frequently detected DRPs. 87% of advice given by the pharmacist was accepted or taken into consideration. Typical questions from the nursing staff were related to drug preparation, generic equivalents and drug administration. Questions from doctors were most frequently related to drug dosage, efficiency and adverse effects.

Conclusions

The addition of a dedicated clinical pharmacist to the ICU team improves the quality and safety of medication in a mixed Norwegian ICU.