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PubMed2007

Erythromycin is more effective than metoclopramide in the treatment of feed intolerance in critical illness.

OBJECTIVE: This study aimed to a) compare the efficacy of metoclopramide and erythromycin in the treatment of feed intolerance in critical illness; and b) determine the effectiveness of "rescue" combination therapy in patients who fail monotherapy. DESIGN: Randomized controlled trial. SETTING: Level III mixed medical and surgical intensive care unit. PATIENTS: Ninety mechanically ventilated, medical patients with feed-intolerance (gastric residual volume>or=250 mL). INTERVENTIONS: Patients received either metoclopramide 10 mg intravenously four times daily (n=45) or erythromycin 200 mg intravenously twice a day (n=45) in a double-blind, randomized fashion. After the first dose, nasogastric feeding was commenced and 6-hourly nasogastric aspirates were performed. If a gastric residual volume>or=250 mL recurred on treatment, open-label, combination therapy was given. Patients were studied for 7 days. Successful feeding was defined as 6-hourly gastric residual volume<250 mL with a feeding rate>or=40 mL/hr. MEASUREMENTS AND MAIN RESULTS: Demographic data, blood glucose levels, and use of inotropes, opioids, and benzodiazepines were similar between the two groups. After 24 hrs of treatment, both monotherapies reduced the mean gastric residual volume (metoclopramide, 830+/-32 mL to 435+/-30 mL, p<.0001; erythromycin, 798+/-33 mL to 201+/-19 mL, p<.0001) and improved the proportion of patients with successful feeding (metoclopramide=62% and erythromycin=87%). Treatment with erythromycin was more effective than metoclopramide, but the effectiveness of both treatments declined rapidly over time. In patients who failed monotherapy, rescue combination therapy was highly effective (day 1=92%) and maintained its effectiveness for the study duration (day 6=67%). High pretreatment gastric residual volume was associated with poor response to prokinetic therapy. CONCLUSIONS: In critical illness, erythromycin is more effective than metoclopramide in treating feed intolerance, but the rapid decline in effectiveness renders both treatments suboptimal. Rescue combination therapy is highly effective, and further study is required to examine its role as the first-line therapy.

Critical Illness↗
PubMed1987

Increased sensitivity to erythromycin in Escherichia coli associated with the presence of the ColV,I-K94 virulence plasmid.

Introduction of the virulence plasmid, ColV,I-K94, into Escherichia coli strains led to increased sensitivity to erythromycin. This was the result of increased passage of antibiotic into ColV,I-K94+ organisms because the plasmid effect was abolished in bacteria which had been made permeable by chemical treatment. Full sensitivity in ColV+ strains appears to depend on the simultaneous presence of transfer and colicin components. Increased erythromycin sensitivity associated with the plasmid was demonstrated in organisms grown at 37 degrees C; the sensitivity of ColV,I-K94+ organisms grown at 25 degrees C was similar to that of the parent strain. Added Mg++ or Ca++ ions reversed erythromycin inhibition in strains with the basal level of sensitivity (i.e., the Col- parent grown at 25 degrees C or 37 degrees C or the ColV,I-K94+ derivative grown at 25 degrees C) and in those with the plasmid-associated increase in sensitivity. Addition of phosphate or EDTA to broth increased erythromycin sensitivity in Col- and ColV,I-K94+ strains although the latter was affected most. Erythromycin was more inhibitory at pH 8.5 than at pH 7.4. This enhanced activity was more marked against the ColV,I-K94+ strain than against the Col- strain. The effects of growth in phosphate-containing medium and at alkaline pH were partially additive. We suggest that ColV,I-K94+ strains may be sensitive to erythromycin because ColV-specified proteins are extruded by a process of "self-promoted transfer" and that the effects of these proteins on the lipopolysaccharide component of the outer membrane facilitates antibiotic influx.

Bacteriocin Plasmids↗
PubMed2002

Is penicillin and/or erythromycin resistance present in clinical isolates of group B streptococcus in our community?

Traditionally group B streptococcus (GBS) has not exhibited resistance to the antibiotics penicillin and erythromycin. Recently there are reports from North America whereby some GBS isolates have exhibited resistance to erythromycin. There have been no studies reported to date to determine whether this resistance trend is also occurring in the Australian population. Over a period of six months from January to June 1999, 250 GBS isolates were collected at the Royal Women's Hospital, Melbourne. Sensitivity to penicillin, erythromycin and vancomycin was determined by disk diffusion. Any isolates that had reduced zones to penicillin, vancomycin or erythromycin had minimum inhibitory concentrations (MIC) determined. No isolates had reduced susceptibility to penicillin or vancomycin. Of the 250 isolates, seven (2.8%, 95% CI = 1.1-5.6%) had resistant MICs to erythromycin of > 1.0 microg/mL. These preliminary data suggest that penicillin therapy is still an effective first-line antibiotic for intrapartum chemoprophylaxis and that erythromycin resistance is low in our population.

Anti-Bacterial Agents↗
PubMed1981

Absorption and bioavailability of oral erythromycin.

1 Extent and rate of absorption of erythromycin were studied in 24 healthy volunteers whose disposition kinetics after i.v. injections had been previously documented. 2 Two clinically attractive oral dosage regimens were administered: erythromycin stearate tablets 1 h before meals (Regimen A), and erythromycin base capsules 30 min after start of meals (Regimen B), each equivalent to erythromycin 250 mg, 6 h apart for 9 doses. 3 Serum concentrations of erythromycin measured during the 1st and 9th (steady-state) dosing intervals resulted in higher maximum serum concentrations for Regimen A (median 1.1, range 0-3.3 and 2.7, 0.6-7.3 mg/l for Doses 1 and 9, respectively) compared with Regimen B (0.4, 0-2.2 and 1.4, 0.2-4.9 mg/l). 4 Absorption occurred earlier with Regimen A with times to maximum concentrations (median, range) being 128, 60-greater than 360 and 118, 75-210 min for doses 1 and 9 respectively, (lag times 75, 15- greater than 360 and 73, 10-110 min) compared with 303, 130-greater than 360 and 173, 45-greater than 360 min (lag times 183, 70-greater than 360 and 190, 20-330 min) for Regimen B. 5 Where it could be assessed, absolute bioavailability for Regimen A was approximately 30% (Dose 1) and 65% (Dose 9) and 40% for both doses of Regimen B. 6 Whereas individual serum concentration-time curves were accurately predicted by the mean for Regimen A, predictability for Regimen B was impossible due to prolonged and variable lag time. 7 The large intersubject variability in erythromycin serum concentration after oral administration, has been shown conclusively to be related to variability in absorption kinetics and absolute bioavailability rather than to variability in disposition kinetics.

Administration, Oral↗
PubMed2004

Characterization of erythromycin resistance in Campylobacter coli and Campylobacter jejuni isolated from pig offal in New Zealand.

AIMS: To determine the level and mechanism(s) of antimicrobial resistance in Campylobacter isolates obtained from human and environmental sources from South Canterbury, New Zealand. METHODS AND RESULTS: A total of 251 Campylobacter isolates were tested for susceptibility to ciprofloxacin, erythromycin, nalidixic acid and tetracycline using disc diffusion assays. Five pig offal isolates were observed to be highly erythromycin resistant, with minimal inhibitory concentrations determined to be >/=256 microg ml(-1). Nucleotide sequencing of the 23S ribosomal DNA (rDNA) in these resistant isolates identified an A --> G change at Escherichia coli position 2059 that has been previously implicated in erythromycin resistance in Campylobacter coli. Macrorestriction profiling using pulsed-field gel electrophoresis showed these isolates were nonclonal. CONCLUSIONS: The majority of Campylobacter isolates from South Canterbury remain sensitive to the most clinically relevant antimicrobial agents. Our results support other reports showing that specific variations in the 23S rDNA contribute to erythromycin resistance. SIGNIFICANCE AND IMPACTS OF THE STUDY: This study defines the baseline frequency of antimicrobial resistance associated with Campylobacter isolates from South Canterbury, and discusses the likely molecular mechanisms conferring erythromycin resistance in this organism. Resistance to erythromycin in these isolates is not linked to a dominant Campylobacter clone and has likely arisen independently in different genetic lines exposed to selective antimicrobial pressure.

Animals↗
PubMed1991

The synthesis of polyphenylalanine on ribosomes to which erythromycin is bound.

Erythromycin binds to the large subunit of Escherichia coli ribosomes at a specific site that is very close to the amino acid of aminoacyl-tRNA bound into the peptidyltransferase center, and to the site to which puromycin is bound, the P and A sites, respectively, of the classical two-site model of ribosome function. Both erythromycin and puromycin affect fluorescence from fluorescent derivatives of aminoacyl-tRNAs, while both puromycin and aminoacyl-tRNAs affect fluorescence of fluorescent derivatives of erythromycylamine. The results demonstrate unequivocally that erythromycin, deacylated tRNA, a peptidyl-tRNA analogue and puromycin can be bound simultaneously to the same ribosome. Nascent peptides of more than a few amino acids in length block binding of erythromycin to the ribosomes but, unlike most other peptides, long polyphenylalanine chains can be synthesized on ribosomes to which erythromycin is bound. It is suggested that this refractory synthesis in the presence of erythromycin reflects the atypical physical and structural properties of polyphenylalanine.

Binding Sites↗
PubMed2003

Oral erythromycin and symptomatic relief of gastroparesis: a systematic review.

OBJECTIVE: Erythromycin is a motilin agonist that greatly increases the fractional rate of gastric emptying. Although a number of studies document the efficacy of erythromycin in improving gastric emptying, little information exists concerning symptom improvement in patients with gastroparesis. The aim of this study was to review clinical trials of erythromycin to determine the efficacy of this agent in producing symptom relief in patients with gastroparesis. METHODS: A MEDLINE search from 1966 to 2001 was performed to identify all clinical trials using erythromycin in patients with gastroparesis. The search was further limited to clinical trials using symptom assessment as an endpoint. References from index citations were reviewed to identify additional studies. The search was conducted independently by two authors, and discrepancies were resolved by consensus opinion. RESULTS: Thirty-five clinical trials were identified, and five met inclusion criteria. One study each involved gastroparesis caused by surgery and systemic sclerosis. Three studies evaluated patients with diabetic or idiopathic gastroparesis. No study used symptoms as a primary endpoint. Improvement was reported in 26 of 60 (43%) patients. Individual symptom scores were available for 23 of 60 subjects in these studies, and symptom improvement was seen in 11 of 23 (48%) patients. One study compared erythromycin and metoclopromide in an open-label, crossover fashion, and found no difference between the two agents. All studies were methodologically weak and highly subject to bias. Four of five studies were open-label trials. Sample sizes in all studies were < or =13 subjects, and treatment duration was < or =4 wk in all studies. CONCLUSIONS: Although clearly a potent prokinetic, limited data exist concerning efficacy of erythromycin in treating gastroparesis. Small sample sizes, uncontrolled designs, short duration, and inadequate symptom assessment limit available studies. Well-designed trials designed to assess symptom relief in gastroparesis are needed.

Administration, Oral↗
PubMed1976

The safety of topical erythromycin.

The prevention of allergic complications depends on the use of topical medications which have proved to be rare sensitizers. This is particularly true for stasis ulcers and eczemas which are notoriously readily sensitized. Topical erythromycin has proved to be such a non-sensitizing topical antibiotic. In a series of 60 patients with stasis ulcers, erythromycin in the form of Ilotycin ointment (erythromycin in petrolatum) was applied. Not a single instance of allergic sensitization occurred. No instances of sensitization with positive patch tests to topical erythromycin have been reported. Maximization tests with topical erythromycin did not produce sensitization. Topical erythromycin, an effective antibiotic, should be substituted for neomycin which is a common sensitizer.

Administration, Topical↗
PubMed1995

Interaction between erythromycin and nitrazepam in healthy volunteers.

Interaction between erythromycin, a strong inhibitor of CYP3A4, and nitrazepam, a long-acting benzodiazepine, was investigated in a double-blind and randomized cross-over study of two phases. Ten healthy volunteers received erythromycin (500 mg x 3) orally or placebo for 6 days. On the fourth day they were given a challenge dose of 5 mg nitrazepam. Plasma samples were collected and psychomotor effects were measured during 42 hr after intake of nitrazepam. There was a statistically significant pharmacokinetic interaction between erythromycin and nitrazepam. Erythromycin increased the area under the nitrazepam concentration-time curve by 25% (P < 0.05) and the peak concentration by 30% (P < 0.05). The concentration peak time of nitrazepam was shortened by over 50% (P < 0.05). The elimination half-lives did not change. Accordingly, as far as the metabolism of nitrazepam is concerned, erythromycin does not cause any major changes in the metabolism of nitrazepam. In psychomotor performance only minor differences were seen. It is concluded that the interaction between erythromycin and nitrazepam is of little clinical significance.

Absorption↗
PubMed1999

Effect of erythromycin and itraconazole on the pharmacokinetics of oral lignocaine.

Lignocaine is metabolized by cytochrome P450 3A4 enzyme (CYP3A4), and has a moderate to high extraction ratio resulting in oral bioavailability of 30%. We have studied the possible effect of two inhibitors of CYP3A4, erythromycin and itraconazole, on the pharmacokinetics of oral lignocaine in nine volunteers using a cross-over study design. The subjects were given erythromycin orally (500 mg three times a day), itraconazole (200 mg once a day) or placebo for four days. On day 4, each subject ingested a single dose of 1 mg/kg of oral lignocaine. Plasma samples were collected until 10 hr and concentrations of lignocaine and its major metabolite, monoethylglycinexylidide were measured by gas chromatography. Both erythromycin and itraconazole increased the area under the lignocaine plasma concentration-time curve [AUC(0-infinity)] and lignocaine peak concentrations by 40-70% (P<0.05). Compared to placebo and itraconazole, erythromycin increased monoethylglycinexylidide peak concentrations by approximately 40% (P<0.01) and AUC(0-infinity) by 60% (P<0.01). The clinical implication of this study is that erythromycin and itraconazole may significantly increase the plasma concentrations and toxicity of oral lignocaine. The extent of the interaction of lignocaine with these CYP3A4 inhibitors was, however, less than that of, e.g. midazolam or buspirone, and it did not correlate with the CYP3A4 inhibiting potency of erythromycin and itraconazole.

Administration, Oral↗
PubMed1991

[A mechanism of usefulness of treatment with erythromycin for diffuse panbronchiolitis].

The clinical usefulness of treatment with erythromycin for diffuse panbronchiolitis (DPB) patients have been well reported to date, although its mechanisms remain unknown. In a previous study, we demonstrated that DPB patients were found to have large percentages of neutrophils in their lower respiratory tracts and suggested that neutrophils play an important role in the pathogenesis of DPB (Chest 99: 917-923, 1990). While in vitro and in vivo studies have demonstrated that erythromycin decreases neutrophils directed migration. In the present study, we performed bronchoalveolar lavage (BAL) on eight patients with DPB to clarify the cell populations in the lower respiratory tract before and after treatment with erythromycin. Neutrophils percentages in BAL fluid were significantly reduced after treatment with erythromycin (54.3 +/- 22.4% to 13.1 +/- 13.5%, p less than 0.01). No significant variance of BAL lymphocyte percentages was demonstrated after treatment with erythromycin. These results suggest that a main mechanism of clinical usefulness of treatment with erythromycin for DPB may be inhibition of neutrophils migration into the lower respiratory tract instead of intrapulmonary bactericidal activity against organisms.

Adolescent↗
PubMed2005

Possible involvement of organic anion transporter 2 on the interaction of theophylline with erythromycin in the human liver.

Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver.

Animals↗
PubMed2004

Pharmacokinetics of erythromycin in rabbit corneas after single-dose infusion: role of P-glycoprotein as a barrier to in vivo ocular drug absorption.

Efflux pump like P-glycoprotein (P-gp) is known to be a major barrier to drug delivery. Functional P-glycoprotein has been recently identified in cornea and corneal cell lines. Thus, it is probable that P-glycoprotein may restrict in vivo ocular drug absorption, resulting in low ocular bioavailability. Experiments were designed using New Zealand albino (New Zealand White) rabbits to assess inhibitors of P-gp efflux to increase drug absorption. Anesthetized rabbits were given constant topical infusions of [(14)C]erythromycin in the presence and absence of inhibitors. Testosterone, verapamil, quinidine, and cyclosporine A were selected as P-gp inhibitors. Transport experiments were conducted in Madin-Darby canine kidney cells transfected with the human mdr1 gene (MDCK-MDR1). Erythromycin exhibited significant efflux out of MDCK-MDR1 cells, suggesting that erythromycin is a good substrate for P-gp. Ocular pharmacokinetic studies were conducted using a topical single-dose infusion method. Maximum inhibition of P-gp mediated efflux was observed with 500 microM testosterone. Area under the curve (AUC)(0- infinity ) of erythromycin with 500 microM testosterone was almost 4 times higher than AUC(0- infinity ) without any inhibitor. Rate of elimination (k(10)) for erythromycin and those with inhibitors was found to be similar (141 +/- 23 min), suggesting that elimination pathways were not altered. All the inhibitors were found to be nontoxic. Verapamil also inhibited the efflux pump with moderate change in AUC(0- infinity ) and C(max) compared with control. Thus, P-gp is found to be active in vivo, and it restricts topical erythromycin absorption across the cornea, which can be inhibited by known P-gp inhibitors. Therefore, ocular bioavailability of P-gp substrates can be significantly enhanced by proper selection of P-gp inhibitors.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Differentiation of arrhythmia risk of the antibacterials moxifloxacin, erythromycin, and telithromycin based on analysis of monophasic action potential duration alternans and cardiac instability.

Antibacterial drugs are known to have varying degrees of cardiovascular liability associated with QT prolongation that can lead to the ventricular arrhythmia torsade de pointes. The purpose of these studies was to compare the assessment for the arrhythmogenic risk of moxifloxacin, erythromycin, and telithromycin. Each drug caused dose-dependent inhibition of the rapidly activating delayed rectifier potassium current encoded by the human ether-á-go-go-related gene (hERG) with IC20 concentrations of 31 microM (moxifloxacin), 21 microM (erythromycin), and 11 microM (telithromycin). These drugs were also evaluated in an anesthetized guinea pig model to measure changes in monophasic action potential duration (MAPD) and to quantify beat-to-beat alternations in MAPD during rapid ventricular pacing. Moxifloxacin dose dependently increased MAPD and caused a rate-dependent increase in alternans at the highest achieved free drug concentration (41 microM). Erythromycin also increased MAPD at its highest free drug concentration (58 microM), but alternans occurred at a relatively lower therapeutic multiple (13.9 microM), and the magnitude of alternans at higher concentrations was independent of pacing rate. Further analysis of the data showed that the beat-to-beat pattern of alternans with erythromycin was less stable than that with moxifloxacin and suggestive of greater arrhythmogenic liability. In contrast to erythromycin and moxifloxacin, telithromycin decreased both MAPD and alternans at the highest achievable drug concentration (7.9 microM). The relative risk at therapeutic concentrations is erythromycin>moxifloxacin>telithromycin and appears to be consistent with clinical observations of torsade de pointes in patients.

Action Potentials↗
PubMed1982

Effects of erythromycin in combination with penicillin, ampicillin, or gentamicin on the growth of Listeria monocytogenes.

Since the optimal antimicrobial therapy for infections caused by Listeria monocytogenes, particularly in patients allergic to penicillin, is uncertain, we investigated the in vitro effects of erythromycin, alone and in combination with other antibiotics, on listeriae. Seven strains of listeriae were inhibited but not killed by erythromycin, penicillin G, or ampicillin when tested by a microtiter broth dilution method. Susceptibility to gentamicin decreased when tryptose phosphate broth was substituted for Mueller-Hinton broth, but was independent of their calcium and magnesium concentrations. Quantitative killing studies performed with erythromycin combined with either penicillin G or ampicillin yielded antagonism for all strains, in contrast to microtiter checkerboard determinations, which did not indicate antagonism in all instances. Antagonism occurred with strains in both the stationary and log phases of growth and was slightly reversed by a 120-min preincubation of the listeriae with penicillin before the addition of erythromycin. Erythromycin and gentamicin were antagonistic in quantitative killing studies. Based on these in vitro findings, we conclude that the addition of gentamicin to erythromycin offers no advantage in the treatment of listeriosis in the penicillin-allergic patient.

Ampicillin↗
PubMed1988

Randomized clinical trial of topical mupirocin versus oral erythromycin for impetigo.

The safety and efficacy of a new topical antiinfective agent, mupirocin, was compared with that of oral erythromycin ethylsuccinate in the treatment of impetigo in children. Sixty-two children aged 5 months to 13 years with impetigo were assigned to be treated with either mupirocin in three daily applications or erythromycin ethylsuccinate (40 mg/kg of body weight per day divided into four doses) according to a randomized treatment schedule. On the initial visit, exudate or cleansed infected sites or both were cultured and therapy was begun. All patients were treated for 8 days. Patients were seen again on days 4 to 5 of therapy, at the end of therapy, and 7 days after the end of therapy. Sites of infection were comparable between the groups, as were bacteriologic responses. At the first visit, 24 of 30 children in the mupirocin group and 14 of 32 children in the erythromycin group were cured or had at least a 75% reduction in size of the lesions. At the end of the study, all 29 of the children in the mupirocin group who came to follow-up, compared with 27 of 29 in the erythromycin group, were cured. Side effects were few. Five children in the erythromycin group developed mild diarrhea. Thus, mupirocin appears to be safe and effective in treating impetigo in children. Our data show a trend toward more rapid clinical response with mupirocin than with erythromycin.

Administration, Oral↗
PubMed1989

Comparative pharmacokinetics of clarithromycin (TE-031), a new macrolide antibiotic, and erythromycin in rats.

Clarithromycin (TE-031) is a newly synthesized macrolide with high stability in acidic conditions. In the present study, the pharmacokinetics of [N-methyl-14C]clarithromycin were compared with those of [N-methyl-14C]erythromycin in rats by radioassay and bioassay. Both radioactivity and bioactivity of [14C]clarithromycin in plasma and tissues were found to be significantly higher than those of [14C]erythromycin at the same oral dose of 20 mg/kg (body weight). Among the tissues, the peak level of [14C]clarithromycin in the lung was especially high. Levels of radioactivity and bioactivity amounted to 15 and 73 times the corresponding levels of [14C]erythromycin. In the urine, bioactivity recovered after administration of [14C]clarithromycin was sevenfold higher than that for [14C]erythromycin. This accounted for about 60 and 20% of the total radioactivity in the urine for [14C]clarithromycin and [14C]erythromycin, respectively. An examination of metabolites in the urine for [14C]clarithromycin revealed appreciable amounts of bioactive unchanged clarithromycin. These results indicate that clarithromycin has pharmacokinetic properties superior to those of erythromycin. The desirable properties of clarithromycin include high levels in plasma resulting from its high stability in gastric acid; a high tissue affinity, especially to the lung; and favorable urinary excretion.

Administration, Oral↗
PubMed1990

Autobacteriographic studies of clarithromycin and erythromycin in mice.

The antimicrobial activity of clarithromycin was compared with that of erythromycin in experimentally infected mice by whole-body autobacteriography. In mice with systemic staphylococcal infections, the number of vital microbes in the body was relatively low in the early period after oral administration of erythromycin, but increased thereafter to the levels found in nonmedicated control mice. On the other hand, with clarithromycin treatment, a significantly smaller number of microbes was evident throughout the body. The microbes were scarcely seen in the parenchyma of any organs during the examination period. This potent antimicrobial activity of clarithromycin compared with that of erythromycin was further demonstrated in mice with respiratory infections. On the other hand, to examine the distribution properties of both antibiotics in the whole body, an autoradiographic study was carried out with [N-methyl-14C]clarithromycin and [N-methyl-14C]erythromycin. Both labeled antibiotics were distributed widely throughout the body after oral administration in both uninfected control mice and mice with systemic infections. However, the radioactivity was more marked and persistent for [14C]clarithromycin than it was for [14C]erythromycin, particularly in the lungs. The observations described above indicate the superior in vivo antimicrobial activity of clarithromycin compared with that of erythromycin and suggest that the superiority of clarithromycin is largely attributed to its favorable distribution properties. The advantages of whole-body autobacteriography, coupled with whole-body autoradiography, are discussed.

Administration, Oral↗