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PubMed1996

An open study to compare azithromycin with cefaclor in the treatment of children with acute otitis media.

An open, multicentre study involving 259 children between 6 months and 13 years of age was performed to assess the efficacy and safety of azithromycin and to compare it with cefaclor as treatment of acute otitis media. Patients were randomized to receive either azithromycin 10 mg/kg once daily for 3 days or cefaclor 40 mg/kg daily in divided doses every 8 h for 10 days. Cure or improvement in signs and symptoms was observed in 112/114 (98%) evaluable azithromycin-treated patients and 116/120 (97%) evaluable cefaclor-treated patients on days 11-15. In contrast to cefaclor, however, azithromycin was associated with a significantly (P = 0.033) higher cure rate 1 month after completion of treatment. In those patients who were followed up to days 25-30, the response was satisfactory (cure or improvement) in 31/32 (97%) patients who had received azithromycin and in 31/36 (86%) to whom cefaclor had been administered. Patients tolerated both treatments well and no severe adverse events related to therapy were recorded in either group. The results of this study show that a 3-day, once-daily regimen of azithromycin has comparable clinical efficacy and tolerability to a thrice-daily course of cefaclor administered for 10 days, but the azithromycin is associated with a lower incidence of relapse.

Acute Disease↗
PubMed1996

Comparative in-vitro activity of cefaclor against urinary tract isolates of Escherichia coli.

Insusceptibility levels of cefaclor and other commonly prescribed antibiotics were determined for 489 consecutive hospital and community-associated urinary tract isolates of Escherichia coli from the Nottingham area of the UK. Significant resistance (MIC of > or = 8 mg/L) to cefaclor was found to be uncommon in the UK, with insusceptibility percentages as low as 1.5% and 1.4% amongst hospital and community isolates, respectively. When compared with other antimicrobials used commonly for treating urinary tract infection, only ciprofloxacin showed greater activity, though cefaclor showed significantly greater in-vitro activity than cephalexin, ampicillin and trimethoprim. Only seven isolates were insusceptible to cefaclor at a concentration of 8 mg/L. Each of these isolates produced a beta-lactamase, but it is unlikely that beta-lactamase production was the sole reason for insusceptibility since these isolates were also insusceptible to co-amoxiclav. Cefaclor compared extremely well with co-amoxiclav against ampicillin-insusceptible isolates, with none of the pharmacokinetic difficulties and considerations associated with the use of beta-lactam:beta-lactamase inhibitor combinations. Cefaclor appears to be a useful cost-effective alternative to current therapeutic options, particularly for long-term low-dose treatment of recurrent urinary tract infection in those geographical areas where the likelihood of resistance to other possible agents is becoming unacceptably high.

Ampicillin↗
PubMed1993

Clarithromycin and cefaclor suspensions in the treatment of acute otitis media in children.

The safety and efficacy of a new oral suspension formulation of clarithromycin were evaluated in this multicenter, Phase III, single blind, comparative trial in 379 children ages 6 months to 12 years with signs or symptoms of acute otitis media. Children were randomized to receive a 10-day course of clarithromycin oral suspension (7.5 mg/kg; maximum, 500 mg) or cefaclor oral suspension (20 mg/kg; maximum, 500 mg) twice daily. Specific clinical response criteria were developed based on pretreatment signs and symptoms and results of tympanometry. Of the 379 enrolled patients 281 (74%) were evaluable (clarithromycin, 150; cefaclor, 131). There were no demographic differences between the two groups. Fifty percent of the patients had 2 to 4 episodes of otitis media (including the current episode) in the past 12 months; 63% of the patients had an infection of moderate severity. Clarithromycin and cefaclor suspensions were similarly effective for the treatment of acute otitis media. Clinical success (cure, cure with effusion or improvement) was achieved in 86% of clarithromycin-treated patients and 90% of cefaclor-treated patients. The majority of bacterial isolates for which susceptibility results were available were fully or moderately susceptible to the study drugs (96% clarithromycin, 92% cefaclor). Both drugs were well-tolerated; adverse events considered probably study drug-related were reported by 30 (15%) of clarithromycin recipients and 31 (17%) of cefaclor recipients. There were no significant differences between the groups in the numbers of patients reporting events that were thought to be related to study medication.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1995

Multinational multicenter controlled trial comparing ceftibuten with cefaclor for the treatment of acute otitis media. Members of the Ceftibuten Otitis Media International Study Group.

A randomized, controlled, single blind clinical trial was conducted in children with acute otitis media to evaluate the safety and efficacy of a 10-day course of therapy with ceftibuten 9 mg/kg taken as a single daily dose, up to a maximum daily dose of 400 mg, compared with cefaclor 40 mg/kg/day in three divided doses, up to a maximum of 1 g/day. Patients were evaluated any time from 1 to 3 days after completion of therapy (posttreatment follow-up). A total of 154 patients (106 ceftibuten, 48 cefaclor) were evaluable for efficacy. Clinical success as determined by resolution (cure) or improvement of signs and symptoms of infection were seen in 89 and 88% of patients treated with ceftibuten and cefaclor, respectively, at the posttreatment follow-up visit. At the extended follow-up visit (any time from 2 to 4 weeks after completion of therapy), clinical success was sustained in 88 and 82% of the ceftibuten-treated and cefaclor-treated patients, respectively. A total of 391 patients (264 ceftibuten, 127 cefaclor) were included in the safety analysis. Treatment-related adverse experiences occurred in 8% of ceftibuten-treated patients and 14% of cefaclor-treated patients. All were mild or moderate and the majority were gastrointestinal. There were no deaths or serious adverse events. The results of this study suggest that ceftibuten is an effective and well-tolerated alternative to other antibiotic therapies for the treatment of children with acute otitis media.

Acute Disease↗
PubMed1991

[Effects of cefixime and cefaclor on pharyngeal flora in children].

Influences of cefixime and cefaclor, oral antibiotics, were studied in 50 children (age range, 11 months to 13 years) with pharyngitis. Daily doses of cefixime were 6 to 10 mg/kg in 25 children and those of cefaclor were 40 to 50 mg/kg in 25 children. Pharyngeal swabs were taken before and after 3 to 7 days of the antibiotic treatment. Pathogenic organisms, such as Streptococcus pyogenes, Haemophilus influenzae and Streptococcus pneumoniae, were isolated in 14 children before and in 1 child after cefixime use. But these bacteria were isolated in 15 children before and in 9 children, and 3 strains of H. influenzae and 3 strains of S. pneumoniae were newly isolated after cefaclor use. An isolation rate of Gram-negative bacilli, such as Acinetobacter spp., were increased after use of cefixime. In both antibiotics, isolation rates of yeasts were slightly increased. An isolation rate of alpha-hemolytic streptococci was increased from 16% to 48% by cefixime treatment and from 24% to 52% by cefaclor treatment. The MIC50 of cefixime and cefaclor against alpha-hemolytic streptococci isolated after treatment was higher than that isolated before. Effects of cefixime and cefaclor was less extensive than that of ampicillin in previous reports.

Adolescent↗
PubMed1983

Prospective comparison of amoxicillin-clavulanic acid and cefaclor in treatment of uncomplicated urinary tract infections.

Patients with acute, uncomplicated urinary tract infections were treated with either amoxicillin-clavulanic acid (A-C) in fixed combination or cefaclor for 10 days in a prospective randomized comparison. The A-C group included 29 women and 1 man (mean age, 25.5 years), and the cefaclor group included 35 women and 1 man (mean age, 24.9 years). The cure rates were 26 (87%) of 30 with A-C and 26 (72%) of 36 with cefaclor (P greater than 0.20). There was one failure in each group, each caused by an isolate resistant to ampicillin. There were one relapse and two reinfections in the A-C group, compared with seven relapses and two reinfections in the cefaclor group. Side effects, including patients started on antibiotics but whose cultures did not confirm urinary tract infections, were diarrhea in 7 (16%) and rash in 1 (2%) of 44 A-C patients, compared with diarrhea in 1 (2%) and yeast vaginitis in 3 (6%) of 48 cefaclor patients. Although the A-C group had a greater proportion of antibody-coated bacterium-positive infections (22 versus 18 with cefaclor), there was a lower recurrence rate with fewer relapses in patients treated with A-C.

Adult↗
PubMed1991

Pharmacokinetic analysis of the effects of different foods on absorption of cefaclor.

Cefaclor is an oral cephalosporin antibiotic which has a broad antibacterial spectrum. The purpose of this study was to investigate the effect of food on the absorption of cefaclor and to analyze kinetically the absorption process of this drug. Cefaclor was given to eight volunteers at five test times: after overnight fasting, after two rice meals (350 and 700 cal [1 cal = 4.184 J]), and after two bread meals (500 and 1,000 cal). Urinary recoveries of cefaclor and concentrations of the drug in plasma were determined for each administration. Areas under the concentration-time curves and urinary recoveries were not affected by food intake, but the maximum concentration of drug in serum was reduced and the time to maximum concentration of drug in serum was prolonged depending on the type and the quantity of the meal. The larger the quantity of the meal, the more the maximum concentration of drug in serum and the time to maximum concentration of drug in serum were affected. The rice meals affected the absorption process of cefaclor more than the bread meals. The concentrations of cefaclor in plasma following administration after overnight fasting were well fitted to a conventional one-compartment model with a first-order absorption process, but those after the other administrations were not fitted to the model. For the pharmacokinetic analysis of those data, it was necessary to introduce a transfer process from administration site to absorption site to the conventional model. The concentrations in plasma after rice and bread meals were best fitted to the model with a zero-order transfer process than to that with a first-order process. The velocity of the transfer process depended on the type and volume of the meal.

Administration, Oral↗
PubMedDate not supplied

Comparison of cefaclor and amoxicillin for acute otitis media with effusion.

A double-blind randomized clinical trial was conducted comparing cefaclor and amoxicillin for the treatment of acute otitis media with effusion in 110 children (150 ears). Each child underwent unilateral or bilateral tympanocentesis and then randomly received a 14-day course of either amoxicillin or cefaclor. Of 57 children in the cefaclor group, only 3 children (5.3%) had persistent or recurrent symptoms during the 14-day course of treatment, as compared to 5 of 53 children (9.4%) in the amoxicillin group, but this difference is not significant. After completion of the 14 days of therapy, 45 of 76 ears (59.2%) of the children in the cefaclor group were effusion-free, as compared to only 28 of 64 ears (43.7%) of the children in the amoxicillin group. When adjusted for age and race, this difference is statistically significant (p = .03). However, the difference between the effect of the two antimicrobials is not statistically significant in children. Cefaclor is a reasonable choice for antimicrobial therapy for acute otitis media with effusion, and from these study findings, it appears that cefaclor may be more effective than amoxicillin in resolving the middle ear effusion at the completion of 14-day therapy.

Acute Disease↗
PubMed1998

A randomized, observer-blind trial of amoxycillin/clavulanate versus cefaclor in the treatment of children with acute otitis media. Augmentin 415 Study Group.

In this randomized, multicenter, observer-blind study, the efficacy, safety and tolerability of amoxycillin/clavulanate and cefaclor were compared in children with a clinical diagnosis of acute otitis media. Patients aged between 1 and 12 years received either amoxycillin/clavulanate (250 mg/62 mg t.i.d., or 125 mg/31 mg t.i.d. if aged under 6 years) or cefaclor (250 mg t.i.d., or 125 mg t.i.d. if aged under 6 years) for 7 days. The amoxycillin/clavulanate regimen was based on a dose of 20/5 mg/kg/day (representing 20 mg amoxycillin plus 5 mg clavulanic acid) in three divided doses. Patients were followed-up at the end of therapy and on days 10-12 and 38-40. At the end of the study (days 38-40), clinical success rates were 91.4% for amoxycillin/clavulanate and 78.6% for cefaclor. The difference was statistically significant (p = 0.008). After the 7 days of treatment, 3 patients (2.9%) in the amoxycillin/clavulanate group had clinical failure, compared with 18 patients (16.1%) in the cefaclor group (p < 0.001). Both treatments were well tolerated and there were no statistically significant differences between the groups in adverse event profiles. The incidence of diarrhea was low (7.0% amoxycillin/clavulanate, 8.4% cefaclor) and was generally of mild or moderate intensity. The study demonstrated that amoxycillin/clavulanate was significantly more effective clinically than cefaclor in the treatment of acute otitis media in children.

Acute Disease↗
PubMed2000

New insight into the clinical pharmacokinetics of cefaclor: tissue penetration.

The serum pharmacokinetic data presented are generally in agreement with those obtained by other authors with both the cefaclor IR (immediate release) and AF (advanced formulation) or MR (modified release) formulations. With the new sustained-release formulation, the time of peak (Tmax) and mean residence time (MRT) values are significantly longer than those observed with the standard cefaclor IR. For the first time the penetration of the MR formulation of cefaclor was determined both in suction blister fluid (SBF) and alveolar epithelial lining fluid (ELF). Cefaclor demonstrated a high tissue distribution, with a high penetration index (PI) into blister fluid, which is at least representative of a relatively large volume of fluid-filled spaces and in part of highly vascularized tissues. SBF and ELF concentrations were higher than blood levels starting at the 4th-6th hour after dose, with longer elimination half-lives from the extravascular compartment than from serum. Cefaclor has a favorable pharmacokinetic profile, especially the new sustained-release formulation, which maintains effective concentrations for a longer time than the IR preparation. The MR formulation improves the kinetic properties of the cefaclor molecule with a prolonged MRT which allows a daily dosage of 750 mg every 12 h.

Aged↗
PubMed2000

Assessment of the susceptibility of Streptococcus pneumoniae to cefaclor and loracarbef in 13 countries.

Between July 1998 and July 1999, 2,644 clinical isolates of Streptococcus pneumoniae were collected from 27 study centers in 13 countries and their susceptibilities to penicillin, cefaclor and loracarbef were determined by E-test" (AB BIODISK, Solna, Sweden). Overall, 96.3% of isolates were penicillin-susceptible (79.8%) or -intermediate (16.6%) (MIC, < or = 1 microg/ml). Rates of penicillin-resistant S. pneumoniae isolation varied widely and were highest in the study centers tested in New Zealand (10.9%), Canada (10.0%), Mexico (9.1%) and the United States (5.1%). Low rates of penicillin-resistance were found in the study centers tested in Russia (0%), Turkey (0%), Brazil (0.5%), Germany (0.6%), Philippines (1.6%), Italy (2.1%), United Kingdom (2.3%), Australia (3.0%) and Poland (3.1%). Using recently published NCCLS interpretative breakpoints (M100-S10, 2000), 87.2% (median) of all isolates tested were cefaclor-susceptible and 87.8% (median) of all isolates tested were loracarbef-susceptible. Of the penicillin-susceptible S. pneumoniae isolates, 99.5% were susceptible to both cefaclor and loracarbef. Susceptibility to cefaclor and loracarbef was also retained by 30.8% and 32.9% of penicillin-intermediate isolates, respectively. These findings are in contrast to recent publications reporting lower cefaclor and loracarbef activities using non-validated interpretative criteria. In conclusion, rates of penicillin resistance among recent clinical isolates of pneumococci remain low in many centers worldwide. Cefaclor and loracarbef demonstrated excellent in vitro activity against recent clinical isolates of penicillin-susceptible and many isolates of penicillin-intermediate S. pneumoniae.

Cefaclor↗
PubMed2004

Reassessment of cefaclor breakpoints for Haemophilus influenzae.

We previously reported that standard methods overestimate cefaclor minimum inhibitory concentrations (MICs) for Streptococcus pneumoniae due to in vitro chemical instability. This study aimed to ascertain if standard methods accurately measure cefaclor MICs to Haemophilus influenzae. Cefuroxime was used as a comparator. Standard NCCLS broth microdilution and E-Test MICs were determined for eight isolates of H. influenzae. Kill curves determined the "bacteriostatic" MIC, defined as the concentration showing no significant growth or kill over six hours taking into account cefaclor instability. On average, cefaclor and cefuroxime bacteriostatic MICs were 0.2 x MIC and 0.6 x MIC determined by NCCLS methodology respectively. The mean MIC determined by NCCLS methodology was 3.0 mg/L for cefaclor and 0.8 mg/L for cefuroxime. Cefaclor MICs by NCCLS methodology were overestimated due to chemical instability over 18-24 hours. The bacteriostatic MICs by kill curve were not significantly different from those of cefuroxime.

Cefaclor↗
PubMed1993

A comparison of cefpodoxime proxetil and cefaclor in the treatment of acute exacerbation of COPD in adults.

In this multicenter, observer-blinded study, 301 patients with signs and symptoms of acute bacterial exacerbation of COPD were randomized (2:1) to receive either cefpodoxime proxetil (200 mg, bid) or cefaclor (250 mg, tid) for 10 days. Clinical and microbiologic evaluations were performed before treatment, during therapy (study days 3 to 5), at the end of therapy (3 to 7 days posttreatment), and at long-term follow-up (4 weeks posttreatment). The most common pretreatment isolates were Haemophilus influenzae, Haemophilus parainfluenzae, and Streptococcus pneumoniae. Significantly (p < 0.001) more bacterial isolates were susceptible in vitro to cefpodoxime (233 of 256, 91 percent) than to cefaclor (215 of 255, 84 percent). There were no statistically significant differences between the two drug regimens in eradication of the initial pathogen (cefpodoxime, 116 of 128, 91 percent; cefaclor, 59 of 64, 92 percent) or end-of-therapy clinical response (cure + proved; cefpodoxime, 99 of 100, 99 percent; cefaclor, 45 of 49, 92 percent) rates for evaluable patients. Both drug treatments were well-tolerated, with a similar incidence of drug-related adverse events (cefpodoxime 11 percent, cefaclor 12 percent). Cefpodoxime (bid) was as safe and effective as cefaclor (tid) in the treatment of acute exacerbation of COPD. The less frequent dosing regimen of cefpodoxime may improve patient compliance compared to those antibiotics that require three or four daily doses.

Acute Disease↗
PubMed1987

Impact of cefaclor on the normal human oropharyngeal and intestinal microflora.

Cefaclor was given orally in doses of 250 mg every 8 h for 7 days to 10 volunteers. Saliva and faecal specimens were taken up to 16 days for cultivation of aerobic and anaerobic microorganisms and for assay of cefaclor. Cefaclor was not detected in saliva or faeces. In the oropharynx only minor changes in the anaerobic part of the microflora were observed. The microflora was normalized within 1 week after the administration of cefaclor had stopped. The aerobic intestinal microflora was unchanged during and after cefaclor administration while a minor impact on the anaerobic intestinal microflora was observed. The anaerobic intestinal flora returned to its normal state within 1 week. No new colonization with cefaclor resistant microorganisms were observed and no side effects were registered during the investigation period.

Adult↗
PubMed2000

The efficacy and safety of cefaclor in respiratory infections amongst Pakistani children.

PURPOSE: To evaluate the efficacy and safety of Cefaclor in respiratory tract infections amongst Pakistani children. PATIENTS AND METHODS: Multicenter, open label and non-comparative study was done to evaluate the response in terms of symptoms (In vivo) and bacterial cultures (In Vitro) to Cefaclor amongst children with respiratory tract infection between the ages 2 months to 12 years. Each patient was asked to visit the doctor on three occasions i.e., Day 0 (Initial evaluation prior to commencement of study), Day 4 (During therapy assessment and confirmation of compliance) and Day 10 (End of therapy assessment and compliance evaluation). Representative swab specimens (Throat swabs, Ear swabs or Sputum) were collected from the infected site on day 0 and day 10 for culture and sensitivity. Patients were also assessed by the evaluators on each visit in terms of clinical symptomatic response and information collected was documented on a prescribed data base form. RESULTS: A total of 160 patients were enrolled in the study, of whom 15 were lost to follow-up between the first and second visit and a further 38 were lost by the 3rd visit. Thus 107 patients completed the study as per protocol. Otitis media and Upper respiratory tract infection were the predominant ailments amongst the cases enrolled. One or more bacteria were isolated in 75 (46%) instances, the maximum number of isolates being from ear swabs of Otitis media patients. Beta haemolytic Streptococcus (group A,C,F,G) seen in 18 cases was the most common pathogen reported followed by Staphylococcus aureus, H. influenzae and Streptococcus pneumoniae in 13,12 and 11 cases respectively. Sensitivity of Cefaclor for bacteria commonly seen in the respiratory tract was greater than 90% in most of the cases. Evaluation of the 42 culture proven cases for patients who completed the study showed that Cefaclor had a 93% efficacy for indicated bacteria and 54% for non-indicated bacteria. In Vivo analysis of Cefaclor (i.e. on the basis of symptomatic response) showed that 96% cases had a symptomatic response by the second visit, which improved to 97% by the third visit. Only 15 non-serious adverse events were observed in 160 patients, none of the cases necessitated discontinuation of drug. Mild gastrointestinal symptom was the most common adverse event reported. CONCLUSION: Cefaclor was found to be a safe and efficacious drug in the treatment of bacterial respiratory tract infections amongst Pakistani children.

Bacterial Infections↗
PubMedDate not supplied

A comparative study of cefaclor vs. amoxicillin/clavulanate in tonsillopharyngitis.

BACKGROUND: Acute pharyngotonsillitis (APT) is one of the most common inflammatory processes of adults and children in an outpatient setting. Increasing failure rates, hypersensitivity to penicillin, the required multiple daily doses and common side effects lead to poor patients compliance and thus inadequate treatment duration, providing therefore ground for considering alternative antimicrobial agents. MATERIAL AND METHODS: This multicenter, randomized, single blind study was undertaken in order to compare efficacy and safety of cefaclor (375 mg BID) and amoxicillin/clavulanate (625 mg BID) in 10 days treatment regiment of ambulatory patients with APT. A total of 200 patients (age range between 12-65 years) with symptoms of APT and positive antigen strep test were enrolled into the study. Clinical and bacteriological responses were assessed after the end of treatment (14th-18th day) and at the follow-up visit (38th-45th day). All GABHS strains, isolated from throat cultures, were tested for in vitro sensitivity to the antibiotics used in the study and no strain was found resistant to both antibiotics. RESULTS: The results indicated that both antibiotics had high--almost 99% effectiveness at the post therapy visit. On the follow up visit an increased tendency of relapses was observed in the amoxicillin/clavulanate treated group, compared to cefaclor treated group (8.33% vs 3.29%). Relative risk of relapse in patients treated with amoxicillin/clavulanate was 2.6 greater compared to cefaclor. There were significantly higher rates of gastrointestinal adverse events in group treated with amoxicillin/clavulanate (29/97 patients; 29.89%) compared to cefaclor (16/95 patients; 16.84%) - p< 0.03. Frequency of other adverse events did not differ significantly between the groups. CONCLUSIONS: Cefaclor and amoxicillin/clavulonate provide a clinically and bacteriologically effective treatment for patients with pharyngotonsillitis caused by GABHS, but cefaclor treatment is significantly safer in regard to gastrointestinal side effects.

Adolescent↗
PubMed2002

Determination of antimicrobial activity of Cefaclor on common respiratory tract pathogens in Pakistan.

OBJECTIVE: To determine the antimicrobial activity of Cefaclor against common respiratory tract pathogens isolated from patients in Pakistan. SETTING: Department of Microbiology, Liaquat National Postgraduate Medical Centre, Karachi. METHOD: A laboratory analysis was done on 466 isolates of respiratory tract pathogens collected from 13 laboratories from all over Pakistan. Antibiotic sensitivity test was done by Kirby Bauer disc diffusion method and MIC of Cefaclor was determined by 'E' test. RESULT: Of the 163 Streptococcus pneumoniae, 87 Moraxella catarrhalis and 216 Haemophilus influenzae > 95% isolates were susceptible to Cefaclor. The MIC 90 of all these pathogens were < 2 ug. CONCLUSION: Resistance of respiratory tract pathogens to the 2nd generation Cephalosporin, Cefaclor is very low. MIC 90 of Cefaclor against all three common respiratory tract pathogens is < 2 ug, which indicates that Cefaclor would be effective in more than 90% of cases infected with these bacteria.

Cefaclor↗
PubMed1979

An evaluation of the toxicity of cefaclor in laboratory animals.

The toxicity of cefaclor, a new orally-administered cephalosporin, was evaluated in laboratory animals given single or multiple doses of the antibiotic. The acute toxicity data for cefaclor in mice, rats, dogs and monkeys were comparable to that previously reported for cephalexin. Rats were maintained on dietary mixtures of cefaclor which provided average daily doses of approximately 230 to 950 mg/kg for 28 days in subacute toxicity tests, and 160 to 675 mg/kg for 1 year in chronic toxicity tests. Treatment-related effects in the above studies were limited to soft stool excretion and caecal dilatation in the subacute test. Effects in dogs given daily oral doses of 50 to 200 mg/kg for 30 days were limited to a transient moderate fall in haemoglobin concentration in the two males at the highest dose. Soft stool excretion and occasional episodes of emesis were observed in dogs given cefaclor for 1 year at oral doses of 100 to 400 mg/kg/day. A reversible thrombocytopenia occurred in one animal at the highest dose. Analysis of various tissue fluids taken 2 hours after the last dose revealed that the concentration of cefaclor in the synovial fluid was approximatley one-half of that in serum. The results of these studies indicate that cefaclor has a low toxic potential in the species tested.

Animals↗