Clarithromycin (CLA), a broad-spectrum macrolide, is a poorly soluble drug with dissolution rate limited absorption. The aim of this investigation was to prepare CLA nanoparticles from a ternary ground mixture in the presence of sodium lauryl sulfate (SLS) and polyvinyl pyrrolidone (PVP) as co-grinding water-soluble compounds, in order to improve the drug dissolution rate. Different weight ratios of CLA: SLS: PVP were ground in a dry process by planetary ball mill using different grinding ball size. Following the dissolution rate study, physical properties of the best dissolved co-ground formulation was studied. The accelerated stability studies were also conducted on the co-ground formulation.The results revealed that the dissolution rate of ternary ground mixtures was much higher than that of the intact drug (p<0.001). Decreasing the grinding ball size and weight with the same rotation speed resulted in particles with decreased dissolution. On the other hand, increasing the PVP concentration in the formulations reduced the drug dissolution. Dissolution efficiencies (DE10 and DE30) for the best dissolved formulation, which consisted of the equal ratio of each co-ground component, were 8.7 and 5 folds higher than the untreated CLA, respectively. This formulation formed nanocrystals with enhanced solubility after dispersing in water. X-ray diffraction, differential scanning calorimetry and infrared spectrophotometry confirmed no chemical interaction and phase transition during the process. Accelerated stability studies confirmed that the co-ground mixture almost remained unchanged in terms of dissolution rate, drug assay and particle size after exposing in stability conditions for three months.

Clarithromycin (CLM) is a member of macrolide family with broad spectrum antibiotic activity. It is practically insoluble in water and its poor solubility is pH dependent. In this study, series of nanosuspensions containing CLM and stabilizer such as HPMC, NaCMC, polysorbate 80, poloxamer 188 and polyvinyl alcohol in various ratios were prepared using sonoprecipitation method. Briefly, CLM was dissolved in acid solution and the pH of solution was raised under sonication and the effects of different stabilizers on particle size of nanoparticles were evaluated. Characterization of nanoparticles in terms of size, polydispersity index, zeta potential, differential scanning calorimetery and dissolution studies was performed. Antimicrobial activity of CLM nanosuspension was compared with coarse powder by using an agar well diffusion method. The results showed that HPMC was more efficient in size reduction of particles and presence of HPMC E5 with ratio of 3: 5 to CLM in formulation led to develop the stable nanosuspension with particle size of 340 nm. The obtained nanosuspension successfully showed enhanced dissolution rate and antimicrobial activity.

Introduction This study investigates the susceptibility and resistance of H. pylori isolates recovered from gastroduodenal patients naive to Clarithromycin. Methods To that end, H. pylori strains were isolated from antral biopsies of pretreatment patients, and antral biopsy specimens were subsequently cultured. Presumptive H. pylori colonies were also confirmed on enriched Brucella agar by biochemical tests, including catalase, oxidase, rapid urease, and the standard polymerase chain reaction (PCR) method. The antimicrobial susceptibility testing was performed by standard disk diffusion methods according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Then, the Epsilometer test (E-test) was used to determine the minimal inhibition concentration (MIC).  Results Of 180 samples, 80 (44%) were positive for urease and were included for further analysis. 65 were also positive in culture base method. The sensitivity test indicated a 23% resistance rate to Clarithromycin among the six Clarithromycin-resistant strains: four have a common form of the A2143G mutation, and two have A2142G mutation. Conclusion The PCR indicated that the level of resistance to Clarithromycin was very similar to the resistance level in Iran.

Introduction. Various medication regimens have been used to eradicate Helicobacter pylori in dialysis patients; however, optimal response to treatment is still a challenge. This study aimed to compare response to H pylori eradication in dialysis and nonuremic patients. Materials and Methods. In a randomized controlled trial, dialysis patients with dyspepsia and confirmed positive endoscopic biopsy for H pylori were compared to nonuremic patients. Participants were randomly assigned to receive Clarithromycin or levofloxacin. H pylori eradication was assessed using stool antigen test 4 weeks later. Results. Forty-four dialysis and 44 nonuremic patients participated in the study. Four dialysis patients and 2 nonuremic patients did not respond to levofloxacin (P =. 35). Six dialysis patients and 4 nonuremic patients did not respond to Clarithromycin (P =. 47). Conclusions. Response rate to H pylori eradication by Clarithromycin and levofloxacin was slightly lower in dialysis patients compare to nonuremic patients. In dialysis patients, response rate to levofloxacin was slightly higher than Clarithromycin, but the results were not significantly different.