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PubMed2000

A comparative efficacy and safety study of clarithromycin, roxithromycin and erythromycin stearate in mild pneumonia.

The efficacy and safety of clarithromycin, roxithromycin and erythromycin stearate in mild pneumonia were compared in an open randomized trial. Eighty-six male patients, doing their obligatory military service, ranging between 19 and 24 years of age (mean 20), were randomly treated: 29 with clarithromycin 500 mg 12-hourly, 30 with roxithromycin 150 mg 12-hourly, and 27 with erythromycin stearate 500 mg 6-hourly, each course being administered for 10 days. Seventy-eight patients were able to be evaluated for efficacy, 28 receiving clarithromycin, 28 roxithromycin, and 22 erythromycin stearate. There were no significant differences among the groups in terms of clinical success rates (clinical cure or improvement: 89% for clarithromycin, 82% for roxithromycin, and 73% for erythromycin stearate, p = 0.32). However, we found that there were significant differences among the groups in terms of clinical cure rates (75% for clarithromycin, 64% for roxithromycin, and 41% for erythromycin stearate, p = 0.04). Adverse events, mostly gastrointestinal, caused discontinuation of treatment in 3.4% of the patients in the clarithromycin group, in 6.6% of the patients in the roxithromycin group, and in 18.5% of the patients in the erythromycin stearate group. The results indicate that there were no statistically significant differences among the three treatment groups in terms of clinical success rates, but that clarithromycin and roxithromycin were better tolerated.

Adult↗
PubMed2004

New mutation points in 23S rRNA gene associated with Helicobacter pylori resistance to clarithromycin in northeast China.

AIM: To investigate the resistance rate of Helicobacter pylori (H pylori ) to clarithromycin, metronidazole, amoxicillin and tetracycline to guide clinical practice, and to study the mechanism of H pylori resistant to clarithromycin. METHODS: Thirty H pylori strains were isolated from the mucosa of peptic ulcer, gastric tumor and chronic gastritis patients, then the minimal inhibitory concentration (MIC) to clarithromycin, metronidazole, amoxicillin and tetracycline was evaluated by E-test method. The sequence analysis of PCR fragments was conducted in 23S rRNA gene of H pylori resistant to clarithromycin to get the resistance mechanism of the bacteria. RESULTS: Among 30 H pylori strains, 7 cases were resistant to clarithromycin, 12 to metronidazole, 2 to tetracycline and no strain was found to be resistant to amoxicillin. The resistance rates were 23.3%, 40%, 6.7% and 0%, respectively. Three new mutation points were found to be related to the clarithromycin resistance in H pylori isolates, which were G2224A, C2245T and T2289C. CONCLUSION: In northeast China, H pylori shows high resistance to metronidazole, while sensitive to amoxicillin. The mechanism of resistance to clarithromycin may be related to the mutation of G2224A, C2245T and T2289C in the 23S rRNA gene.

Anti-Bacterial Agents↗
PubMed1994

Clarithromycin therapy for bacteremic Mycobacterium avium complex disease. A randomized, double-blind, dose-ranging study in patients with AIDS. AIDS Clinical Trials Group Protocol 157 Study Team.

OBJECTIVE: To determine the antimicrobial activity and tolerability of clarithromycin for treating bacteremic Mycobacterium avium complex disease in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A randomized, double-blind, dose-ranging study. SETTING: Outpatient clinics. PATIENTS: 154 patients with human immunodeficiency virus (HIV) infection and blood cultures positive for M. avium complex who had symptomatic disease. INTERVENTIONS: Random assignment to clarithromycin at dosages of 500 mg, 1000 mg, or 2000 mg twice daily for 12 weeks. MAIN OUTCOME MEASURE: Median number of colony-forming units of M. avium complex per milliliter of blood. RESULTS: Clarithromycin decreased mycobacterial CFUs from 2.7 to 2.8 log 10/mL of blood at baseline to less than 0 log 10/mL during follow-up (P < 0.0001). After 2 weeks, patients receiving 500 mg twice daily were less likely to be culture negative than were patients receiving 1000 or 2000 mg twice daily (11% compared with 33% or 29%; P = 0.08). At 6 weeks, the median number of CFUs of M. avium complex/mL of blood was 0 or 1 for all three groups. Clarithromycin-resistant isolates of M. avium complex developed in 46% of patients at a median of 16 weeks. Median survival was longer in patients assigned to 500 mg twice daily (median, 249 days) than in patients assigned to 1000 mg or 2000 mg. Death in the first 12 weeks was lowest in the 500-mg group (P = 0.007). CONCLUSIONS: Clarithromycin therapy acutely decreased M. avium complex bacteremia in patients with HIV infection by more than 99%. Clarithromycin, 500 mg twice daily, was well tolerated and associated with better survival. Emergence of clarithromycin-resistant organisms was an important problem.

AIDS-Related Opportunistic Infections↗
PubMed1999

[A case of acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin].

Theophylline toxicity has been recognized since its introduction into clinical medicine. Clarithromycin is a new oral macrolide antibiotic with excellent antibacterial activity and rare adverse effect. Patients with upper respiratory infection are often treated with theophylline and clarithromycin concurrently. We report a case of acute renal failure due to acute rhabdomyolysis caused by the interaction of theophylline and clarithromycin. A 72-year-old man visited our hospital because of coughing and a sore throat continuing for 1 week. He was diagnosed as having the common cold with a bronchial asthmatic symptom and was prescribed 200 mg/day of sustained-release theophylline for the treatment of asthma for 7 days. One week later, he visited our hospital again. Radiographic study of the chest revealed mild interstitial pneumonia and 200 mg/day of sustained-release theophylline and 400 mg/day of clarithromycin were administrated concomitantly. Five days after the second visit, the patient was admitted to our hospital because of generalized twitching, muscular weakness, high fever and serious general condition. He experienced generalized muscular twitching and tremor. Blood urea nitrogen was 106.1 mg/dl, serum creatinine was 7.4 mg/dl, serum creatinine kinase (CK) was 36,000 IU/l (normal 15-130 IU/l), CK isozyme revealed the following ratio: BB 0%, MB 1% and MM 99%. He was diagnosed as having acute renal failure with rhabdomyolysis caused by the interaction of theophylline and clarithromycin. Hemodialysis therapy was started. After 5 weeks, his serum creatinine was markedly decreased. It is well-known that clarithromycin enhances the serum concentration of theophylline by inhibition of the cytochrome P450-dependent pathway in hepatocytes. Theophylline toxicity may be enhanced when clarithromycin is administrated concomitantly, especially to elderly patients with dehydration.

Acute Kidney Injury↗
PubMed2000

Assessment of the effect of oral clarithromycin on visual outcome following presumed bacterial endophthalmitis.

PURPOSE: The use of clarithromycin was assessed as a biofilm reducing agent in the management of bacterial endophthalmitis. METHODS: 84 eyes of 83 patients presenting with clinical signs highly suggestive of bacterial endophthalmitis were treated using a standard regimen of intraocular vancomycin, amikacin and systemic steroids, which in addition included oral clarithromycin. Ocular penetration of oral clarithromycin in healthy and inflamed eyes was also assessed. RESULTS: Comparing visual acuities at presentation and 6 months, 66% of patients demonstrated an improvement. Intraocular samples were culture positive in 58% of eyes. As compared to culture positive cases, more culture negative cases achieved a visual acuity of 6/12 or better (p = 0.0047). As compared to patients receiving the standard protocol but without clarithromycin, a greater number of culture negative cases demonstrated an improvement in vision of > or = + 6 Snellen lines (p = 0.023). The ocular penetration of clarithromycin into the anterior chamber of inflamed eyes appears sufficient to allow anti-biofilm activity against bacteria at the basic pH encountered in eyes with endophthalmitis. CONCLUSIONS: The ocular penetration of clarithromycin appears adequate for anti-biofilm activity in inflamed eyes. The beneficial effects of oral clarithromycin on visual outcome has been demonstrated in culture negative eyes with clinical signs highly suggestive of bacterial endophthalmitis. The final visual outcome for culture positive cases remains poor.

Administration, Oral↗
PubMed2003

Cefaclor AF vs Clarithromycin in acute exacerbation of chronic bronchitis (B3M-PK-AJBG).

OBJECTIVE: To compare the efficacy and safety of Cefaclor AF vs Clarithromycin in the treatment of acute exacerbation of chronic bronchitis in adult subjects. PATIENTS AND METHODS: This study was conducted on 300 patients suffering from acute exacerbation of chronic bronchitis, who attended the out patient clinics of ten different hospitals throughout Pakistan. Pneumonia, bronchiectasis and tuberculosis were excluded with the help of chest radiography and sputum smear examination. Pretherapy sputum culture and sensitivity (c/s) were tested and patients were randomized and supplied with either tablet Cefaclor 375 mg or tablet Clarithromycin 250 mg to be taken twice daily. Patients were evaluated at day 0 and then at day 3-5 and day 10-11. Post therapy sputum c/s was done on day 10-11. A fourth and final visit was planned on day 20-24 which was optional. At each visit, the severity of disease and the signs and symptoms were recorded on the clinical report forms according to the preset standards. RESULTS: Of 136 patients in the Cefaclor group and 142 patients in the Clarithromycin group, cure was achieved in 44 vs 35 subjects, improvement in 78 vs 91 subjects and failure in 16 vs 18 subjects among Cefaclor vs Clarithromycin groups respectively. The overall clinical efficacy (cure and improvement combined ) was 88.4% in the Cefaclor group and 87.5% in the Clarithromycin group. Nine patients in the Cefaclor group and patients in the Clarithromycin group had one adverse event whereas twelve patients in each group had two or more adverse events. CONCLUSIONS: The above results show that both Cefaclor AF and Clarithromycin are equally effective and safe in the treatment of acute exacerbation of chronic bronchitis in adult patients.

Acute Disease↗
PubMed2004

[Prevalence and mechanism of Helicobacter pylori resistance to clarithromycin in children].

OBJECTIVE: To investigate the prevalence of Helicobacter pylori (H. pylori) resistance to clarithromycin (CLM) in children and to demonstrate the correlation of 23S rRNA gene mutation to clarithromycin resistance of Helicobacter pylori isolates. METHODS: Totally 108 clinical strains of H. pylori were isolated from gastric biopsy specimens obtained from children who underwent endoscopy during the period from October 2002 to January 2004 in Children's Hospital Affiliated to Medical College of Zhejiang University. H. pylori was identified by morphology and biochemical tests after culture. Clarithromycin susceptibility of H. pylori isolates was determined by both E-test and two-fold agar dilution method. A strain was considered resistant when the MIC was defined as >or= 1 microg/ml. Genome DNAs of the 108 isolates were extracted and prepared for PCR to detect the corresponding gene in the V domain of the 23S rRNA. The amplified fragments were recognized and analyzed by restriction fragment length polymorphism (RFLP) when an additional restriction site is created by the mutation. The PCR products of all sensitive and resistant strains were digested with restriction enzyme BbsI and BsaI and were analyzed on a 1.5% agarose gel to discriminate different kinds of mutant genotype. RESULTS: Sixteen of 108 isolates of H. pylori were resistant to clarithromycin by the agar dilution method and E-test method in clinical isolates from children, and the CLM resistance rate was 14.8% (16/108) with MICs ranging from 1 microg/ml to 128 microg/ml. Comparison of results of the two methods showed that these two methods were quite consistent in determination of susceptibility and resistance. The target fragment 425 bp in length containing 23S rRNA corresponding gene was successfully amplified. An A2144G mutation digested with BsaI was detected in 13 resistant isolates, but an A2143G mutation digested with BbsI in only 3 among all 16 clarithromycin resistant strains. None of the sensitive isolates was cleaved by either BsaI or BbsI enzyme, indicating that there was no mutation on them. It was also found that all the fragments from the resistant strains were not completely digested, and 425 bp uncut fragments were also visible and showed three bands indicating that they were heterozygotic strains with a mixture of wild-types and A-->G genotypes. In addition, in this study, no statistically significant difference between mutations at positions 2143 and 2144 with respect to the MIC was observed (r = 0.035, P > 0.05). CONCLUSION: A high prevalence of clarithromycin-resistant H. pylori strains were detected among strains isolated from Chinese children studied. The 23S rRNA gene mutation at positions A2143G and A2144G plays an important role in clarithromycin resistance of H. pylori and A2144G mutation is the predominant finding among the resistant strains.

Anti-Bacterial Agents↗
PubMed2004

[Polarographic catalytic wave of clarithromycin and its applications].

AIM: To develop a new method for the determination of clarithromycin. METHODS: The catalytic wave of clarithromycin in the presence of K2S2O8 was used for improving the analytical sensitivity. The rapid determination of clarithromycin has been carried out by linear single sweep polarography. RESULTS: The reduction wave of clarithromycin appeared at ca. -0.79 V (vs SCE) in 0.24 mol x L(-1) KH2PO4-Na2HPO4 (pH 6.81) supporting electrolyte, which was ascribed to the reduction of carbonyl group on C-9 position. In the presence of 0.01 mol x L(-1) K2S2O8, the reduction wave was catalyzed to produce a parallel catalytic wave. The peak current of the catalytic wave was ca. Twenty times higher than that of the corresponding reduction wave. Based on the catalytic wave, a new method for the determination of clarithromycin has been proposed. The peak current of the catalytic wave was rectilinear to clarithromycin concentration in the range of 4.0 x 10(-7)-5.0 x 10(-5) mol x L(-1). The detection limit was 2.0 x 10(-7) mol x L(-1). CONCLUSION: The proposed method could be used for the direct determination of clarithromycin in pharmaceuticals and urine without preliminary separation.

Anti-Bacterial Agents↗
PubMed2004

Recent success of pantoprazole -or lansoprazole- based clarithromycin plus amoxicillin treatment in the eradication of Helicobacter pylori.

BACKGROUND/AIMS: There are some reports showing that resistance of Helicobacter pylori (H. pylori) to clarithromycin has increased in recent years. We aimed to investigate the current success of a most popular first-line eradication regimen by using two different proton pump inhibitors: lansoprazole and pantoprazole. METHODS: Ninety patients with H. pylori-positive functional dyspepsia were randomized to receive pantoprazole 40 mg b.i.d. or lansoprazole 30 mg b.i.d. in addition to amoxicillin 1,000 mg and clarithromycin 500 mg twice daily for 14 days in a multicenter study. H. pylori infection was determined by histological examination and a rapid urease test. A follow-up endoscopy was performed to assess the H. pylori eradication six weeks after the end of therapy. RESULTS: Seventy-nine patients completed the study protocol properly. The H. pylori eradication rates according to per protocol analysis were 70% in group pantoprazole, amoxicillin and clarithromycin (28/40) and 69.2% in group pantoprazole, amoxicillin and clarithromycin (27/39). The eradication rates according to intention to treat analysis were 62.2% and 60% in lansoprazole, amoxicillin, clarithromycin, pantoprazole, amoxicillin, clarithromycin groups, respectively. The eradication rates were similar in both protocols (p>0.05). CONCLUSIONS: The most popular first-line eradication protocols of H. pylori achieved only a moderate success in the current study. Alternative therapy options are needed instead of clarithromycin-based triple treatment for eradication of H. pylori. The choice of proton pump inhibitor is not important in the eradication rate of H. pylori.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1989

Effects of clarithromycin on cytochrome P-450. Comparison with other macrolides.

Repeated administration of clarithromycin (0.5 mmol.kg-1 p.o. daily for 5 days) to rats increased markedly the same cytochrome P-450 isoenzyme (P-450p) as that induced by troleandomycin. Clarithromycin, however, did not form cytochrome P-450 Fe(II)-metabolite complexes in vitro with microsomes from clarithromycin-treated rats or in vivo after repeated doses of clarithromycin. Nevertheless, clarithromycin formed cytochrome P-450 Fe(II)-metabolite complexes with microsomes from dexamethasone-treated rats in vitro, or after administration to dexamethasone-treated rats in vivo. Similar effects were observed with roxithromycin. In contrast, erythromycin and troleandomycin formed metabolic complexes when given alone, whereas josamycin, midecamycin and spiramycin did not form complexes, even in dexamethasone-treated rats. We conclude that clarithromycin and roxithromycin induce cytochrome P-450p, but do not form complexes with this isoenzyme, although they do form complexes with other glucocorticoid-inducible isoenzymes. We propose that macrolides may be classified into three groups, those forming complexes when given alone (e.g., erythromycin and troleandomycin), those forming complexes only in glucocorticoid-pretreated rats (clarithromycin and roxithromycin) and those not forming complexes (josamycin, midecamycin and spiramycin).

Animals↗
PubMed1988

Effect of dosing intervals on efficacy of clarithromycin and erythromycin in mouse infection models.

Clarithromycin is a new macrolide with a serum half-life which is at least twice that of erythromycin. In order to select the appropriate dosing intervals, the in vitro post-antibiotic effect (PAE) of clarithromycin and erythromycin were compared and the efficacies of clarithromycin and erythromycin when administered once (q.d.), twice (b.i.d.) and three (t.i.d.) times a day in mouse protection tests were measured. The doses were selected from achievable peak serum concentrations in man and were 18 mg/kg for clarithromycin which gave a peak blood level of 2.0 micrograms/ml and a serum half-life of 0.82 h, and 10 mg/kg for erythromycin which gave a peak blood level of 0.9 microgram/ml and a serum half-life of 0.46 h. The PAE of clarithromycin for Staph. aureus is 6.25 h compared to 2.35 h for erythromycin. Clarithromycin was effective against Staph. aureus, Strep. pyogenes and Strep. pneumoniae when administered q.d., b.i.d. and t.i.d. and there was no difference in the cumulative mortalities in the three treatment groups. For erythromycin, there was also no difference in the survival of Strep. pyogenes and Strep. pneumoniae-infected mice, but when tested against Staph. aureus it was more effective when administered t.i.d. than b.i.d., and b.i.d. was more effective than q.d. Clarithromycin administered q.d. was more effective than erythromycin administered t.i.d. against Staph. aureus.

Animals↗
PubMed1995

A randomized comparative study on the safety and efficacy of clarithromycin and erythromycin in treating community-acquired pneumonia.

BACKGROUND: Clarithromycin, a new macrolide, has distinct microbiological and pharmacokinetic advantages compared with erythromycin. This study was designed to compare the safety and efficacy of clarithromycin and erythromycin in the treatment of community-acquired pneumonia. METHODS: Forty adult patients, diagnosed with community-acquired pneumonia, were randomly arranged to received either clarithromycin 250 mg twice daily (20 patients) or erythromycin 500 mg four times daily (20 patients), over a period of 14 days each. RESULTS: There were no statistically significant differences between the two groups in terms of clinical cure (65% for clarithromycin, 65% for erythromycin), clinical success (clinical cure and improvement: 95% for clarithromycin, 90% for erythromycin) and radiological response (95% for clarithromycin, 90% for erythromycin). However, adverse effects, mainly gastrointestinal, were significantly higher among patients treated with erythromycin than among patients treated with clarithromycion (p < 0.05). CONCLUSIONS: These results demonstrate that clarithromycin 250 mg twice daily is at least as effective as erythromycin 500 mg four times daily for the treatment of community-acquired pneumonia, and is much better tolerated.

Adolescent↗
PubMedDate not supplied

Possible role of the intestinal P-450 enzyme system in a cyclosporine-clarithromycin interaction.

Clarithromycin is a macrolide antibiotic similar in structure to erythromycin, but suggested to have fewer drug interactions. Although a pharmacokinetic interaction between clarithromycin and cyclosporine was recently reported, its magnitude and mechanism have not been explored. A 43-year-old renal transplant recipient receiving cyclosporine was treated with clarithromycin because of pneumonia. A cyclosporine pharmacokinetic study was performed 8 days after the initiation of the clarithromycin and 14 days after stopping the drug. Clarithromycin coadministration caused an approximately 2-fold increase in the area under the whole blood concentration versus time curve of cyclosporine. The oral clearance of cyclosporine was halved by clarithromycin, but the terminal elimination rate constant decreased only 15% and mean residence time 20%. These observations suggest that clarithromycin inhibits not only the hepatic metabolism but also the intestinal metabolism of cyclosporine. Caution is advised when administering the two drugs concurrently, and additional studies are necessary to elucidate the mechanism of this interaction.

Adult↗
PubMed1995

[Effect of clarithromycin on symptoms and mucociliary transport in patients with sino-bronchial syndrome].

The effect of clarithromycin on symptoms and on mucociliary transport (as assessed by the saccharin test) were studied in 32 patients with sino-bronchial syndrome. Before treatment with clarithromycin, the nasal clearance time was significantly longer in these patients (70.3 +/- 64.7 min, mean +/- SD) than in control subjects (11.9 +/- 5.3 min, p < 0.001). By the end of 4 weeks of treatment with oral clarithromycin (400 mg/day), nasal clearance time in the patients had improved significantly (30.4 +/- 39.5 min, p < 0.001). Before clarithromycin therapy, bacteria were found in cultures of sputum from 15 patients. After clarithromycin therapy, bacteria were found in cultures of sputum from only 3 of those 15 patients. Cough frequency, volume of sputum, and dyspnea on exertion were significantly improved by clarithromycin therapy. These findings suggest that mucociliary transport is abnormal in patients with sino-bronchial syndrome, and that clarithromycin can be clinically useful in these patients.

Adult↗
PubMed2002

Oral clarithromycin enhances gallbladder emptying induced by a mixed meal in healthy subjects.

Background: In humans, erythromycin has been demonstrated to accelerate gallbladder emptying due to its motilin-like effects on the gastrointestinal tract. Recently, it was shown that clarithromycin, another macrolide, used for the eradication of Helicobacter pylori infection, also stimulated gastrointestinal motility in the fasting state. We conducted a comparative study on the effects of a single oral dose of clarithromycin and of erythromycin on gallbladder emptying in healthy subjects. Methods: Gallbladder emptying variables (residual volume, ejection fraction, area under emptying curve) were measured by ultrasound in 21 healthy subjects (11 males, 10 females, mean age 42.5+/-10.6 years). A test meal (14 g fat, 425 kcal) was ingested 30 min after a single oral dose (500 mg) of either clarithromycin or erythromycin, and the measurements were repeated the following day with the other drug (cross-over double-blind study). A control group consisting of 12 subjects (seven males, five females, mean age 50.7+/-8.2 years) was used to evaluate gallbladder emptying following the same test meal without drug administration. Differences between groups were analyzed using two-tailed Student's t-test for unpaired observations. Results: Gallbladder emptying at 60, 75, and 90 min was greater after erythromycin (P<0.05 at 90 min) and clarithromycin than it was in controls. The ejection fraction was significantly greater after clarithromycin (76.5%) and erythromycin (79.7%) than it was in controls. Gallbladder refilling occurred earlier after clarithromycin than after erythromycin. Conclusions: The prokinetic effect of clarithromycin on the gallbladder appears to be of similar amplitude but of shorter duration than that of erythromycin.

Journal Article↗
PubMed1993

Multicenter comparison of clarithromycin and amoxicillin in the treatment of acute maxillary sinusitis.

PURPOSE: To compare the safety and efficacy of orally administered clarithromycin, a new macrolide antimicrobial, and amoxicillin in the treatment of patients with acute maxillary sinusitis. PATIENTS AND METHODS: One hundred forty-two consecutive outpatients treated at four primary care centers for acute maxillary sinusitis were randomly assigned to receive oral clarithromycin (500 mg twice daily) or oral amoxicillin (500 mg three times daily) for 7 to 14 days. Clinical and roentgenographic responses to the antibiotic therapy were determined within 48 hours after the last dose and 6 weeks later. RESULTS: The success rates of clarithromycin and amoxicillin were comparable. A clinical success rate of 91% and a roentgenographic success rate of 78% were achieved in the clarithromycin group at the final visit; comparable results for the amoxicillin group were 89% and 92%, respectively. Differences between the two groups were not statistically significant (P = .766 and .064, respectively). No serious adverse events were reported, although both drugs caused mild gastrointestinal distress. Dropout rates were low in both groups: 3% for clarithromycin and 4% for amoxicillin. No clinically significant changes in laboratory studies were observed in either group. CONCLUSION: Clarithromycin twice daily is effective and well tolerated in patients with acute maxillary sinusitis.

Acute Disease↗
PubMed2004

Comparative efficacy of topical gatifloxacin with ciprofloxacin, amikacin, and clarithromycin in the treatment of experimental Mycobacterium chelonae keratitis.

OBJECTIVE: To determine the comparative efficacy of topical gatifloxacin with ciprofloxacin, fortified amikacin, and clarithromycin against Mycobacterium chelonae keratitis in an animal model. METHODS: Experimental M chelonae keratitis was induced via intrastromal inoculation in a rabbit model. Thirty-five rabbits were randomly divided into 5 groups and each group was treated hourly for 12 hours with topical 0.9% balanced salt solution, 0.3% gatifloxacin, 0.3% ciprofloxacin hydrochloride, a combination of topical fortified amikacin sulfate (50 mg/mL) and clarithromycin (10 mg/mL), or a triple combination of topical 0.3% gatifloxacin, fortified amikacin sulfate (50 mg/mL), and clarithromycin (10 mg/mL). Antibacterial efficacy of each regimen was determined by quantitative bacteriologic analysis. RESULTS: Treatment with 0.3% gatifloxacin or the triple combination of 0.3% gatifloxacin, topical fortified amikacin sulfate (50 mg/mL), and clarithromycin (10 mg/mL) reduced the number of mycobacterial organisms more significantly than the controls that were treated with a topical balanced salt solution (both P<.001). Therapy with 0.3% gatifloxacin was more effective than 0.3% ciprofloxacin alone (P<.001) and demonstrated synergy by enhancing the efficacy of the combination of fortified amikacin (50 mg/mL) and clarithromycin (10 mg/mL) (P<.001). Neither 0.3% ciprofloxacin nor the combination of fortified amikacin (50 mg/mL) and clarithromycin (10 mg/mL) demonstrated a significant difference in activity against mycobacteria compared with the topical balanced salt solution. CONCLUSION: These results suggest that topical 0.3% gatifloxacin ophthalmic solution can be a new initial treatment agent against M chelonae keratitis.Clinical Relevance Topical gatifloxacin 0.3% may provide an initial alternative in therapy of M chelonae keratitis.

Administration, Topical↗
PubMed1998

Characteristic difference in gastrointestinal excretion of clarithromycin and roxithromycin.

Excretion characteristics of two new macrolides; clarithromycin and roxithromycin, into the intestinal and the gastric lumens was studied by in situ single-pass perfusion and loop methods in rats. Roxithromycin maintained higher serum levels than clarithromycin after their intravenous administrations at a dose of 5 mg kg(-1) each. Radioactivities of clarithromycin and roxithromycin exsorbed into the intestinal lumen were 8.6 and 18.9% of dose in 2 h, respectively, whereas clarithromycin and roxithromycin excreted into the bile were 28.4 and 5.9%, respectively. These results suggest that roxithromycin is transported mainly by exsorption across the intestinal membrane, whereas clarithromycin mainly by excretion through the biliary tract. On the other hand, radioactivities of clarithromycin and roxithromycin exsorbed into the gastric lumen were much less then those into the intestinal lumen and were 0.72 and 1.34% of dose in 4 h, respectively. Thus, the exsorption into the gastric lumen seems to be a minor route for the elimination of both macrolides. Consequently, the transport into the intestinal lumen via the intestinal membrane and/or the bile tract may play a significant role in the overall elimination of both macrolides.

Animals↗