Disposition kinetics of cephradine in normal and Escherichia coli infected goats

The pharmacokinetics of cephradine was studied following single and repeated intramuscular injections in normal and Escherichia coli infected goats. Bioavailability of cephradine was determined in normal goats after a single intramuscular dose. The serum concentrations of cephradine following a single and repeated intramuscular administration of 10 mg/kg b.wt. twice daily for five consecutive days, peaked 2 hours after each intramuscular dose with a lower significant value recorded in E. coli infected goats than in normal goats. The absorption half-lives (t0.5(ab)) following a single intramuscular injection of cephradine was significantly higher in E. coli infected goats (1.18 h) than in normal goats (0.64 h). The elimination half-lives (t0.5(beta)) of cephradine were significantly higher in E. coli infected goats than in normal goats following the administration of fifth and ninth doses. The urine and milk concentrations of cephradine were significantly lower in E. coli infected goats than in normal goats. The mean systemic bioavailability of cephradine following a single intramuscular injection in normal goats was 73.9%.

In vivo release of water-soluble drugs from stabilized water-in-oil-in-water (W/O/W) type multiple emulsions following intravenous administrations using rats

The in vivo release of four water-soluble drugs, cefadroxil, cephradine, antipyrine and 4-aminoantipyrine, from a stabilizing water-in-oil-in-water (W/O/W) type multiple emulsion was studied using rats. The W/O/W type multiple emulsion used in this study could be stabilized for 30 d after preparation at room temperature and also for 24 h in pH 7.4 isotonic phosphate buffer or in rat plasma at 37 degrees C. The cefadroxil and cephradine concentrations in rat plasma following intravenous administrations of their W/O/W type multiple emulsions containing drugs were considerably prolonged compared with those of respective aqueous solutions. Sustained-releasing properties of cefadroxil and cephradine from W/O/W type multiple emulsions could be explained by the mechanism underlying the long residence time of W/O/W type multiple emulsions and delay-release of drugs from the W/O/W type multiple emulsions circulated with rat blood stream. However, antipyrine and 4-aminoantipyrine decreased rapidly following W/O/W type multiple emulsions and these plasma profiles coincided precisely with those following intravenous administration of the aqueous solutions of drugs. These in vivo releasing data correlated with in vitro drug release observation stated in the previous papers.

Peptide carrier-mediated transport in intestinal brush border membrane vesicles of rats and rabbits: cephradine uptake and inhibition

The uptake kinetics of cephradine, an amino-beta-lactam antibiotic, were studied in rat and rabbit intestinal brush border membrane vesicles preparations using both the Ca2+ and the Mg2+ methods of preparation, in the presence of an inward proton gradient. The Ca2+ method demonstrated greater uptake of cephradine in intestinal brush border vesicles prepared from both rat and rabbit and was used for these studies. The transport was observed to be of Michaelis-Menten carrier-mediated type with a passive transport component. The kinetic parameters obtained were as follows: for rat and rabbit, respectively, Km, 1.6 and 1.9 mM; Jmax', 1.7 and 20.7 nmol/mg/min; Pc' (= Jmax'/Km), 1.1 and 10.9 microL/mg/min; and Pm', 0.4 and 0.8 microL/mg/min. The kinetic parameters for the rat vesicles are consistent with those from our previous perfusion study using a conversion factor of 0.71 cm2/mg protein. The rabbit vesicles exhibited a similar Michaelis constant and a 10-fold larger maximal transport velocity, suggesting a quantitative advantage for the study of carrier-mediated transport in the rabbit compared to rat vesicles from the intestine. Cephradine uptake was inhibited by phenylpropionylproline, a proline derivative, and enalapril, an ACE inhibitor, which do not have an alpha-amino group, as well as dipeptides, tripeptides, and amino-beta-lactam antibiotics in both rat and rabbit vesicles. These results support the suggestion that they share the same peptide carrier pathway for oral absorption and that the vesicles may be a useful tool in developing orally effective peptide-type drugs.

Copolymers of lysine and polyethylene glycol: a new family of functionalized drug carriers

Poly(PEG-Lys), a new, water-soluble poly(ether urethane), derived from L-lysine and poly(ethylene glycol) was investigated as a precursor for the preparation of polymeric drug conjugates. To facilitate a wide variety of coupling chemistries, the pendent carboxyl groups of poly(PEG-Lys) were converted to other reactive functional groups (amino, hydroxyl, active ester, and aldehyde) in high yield. These reactive pendent chains were then used as anchors for the covalent attachment of penicillin V and cephradine, two clinically used antimicrobial agents. Coupling to the carrier was achieved in good yields and the chemical versatility of this system was demonstrated by the preparation of conjugates having antibiotic ligands linked via biostable or biodegradable linkages to the carrier, either directly or via a spacer. Conjugate 4, poly(PEG-Lys-penicillin V ester), was obtained by linking penicillin V to the polymer backbone via hydrolytically labile ester bonds. This conjugate exhibited activity similar to that of the parent drug against three clinically important strains of bacteria. Drug activity coincided with the release of the drug from the carrier. Hydrolytically stable cephradine-containing conjugates were prepared by three different coupling methods but showed no antibiotic activity. 14C-labeled poly(PEG-Lys) was injected into mice and its biodistribution was monitored for 48 h. The carrier showed no preferential uptake by liver, spleen, or kidney. No signs of acute toxicity were evident in mice or rats when poly(PEG-Lys) was administered iv and ip at doses up to 10 g/kg. These results indicate that poly(PEG-Lys) is a promising precursor for the preparation of soluble drug conjugates.

[Preparation of stable W/O/W type multiple emulsion containing water-soluble drugs and in vitro evaluation of its drug-releasing properties]

The stable water-in-oil-in-water (W/O/W) multiple emulsion was prepared by a two-step procedure for emulsification using glyceryl tricaprylate (Panasate-800) as the oil phase. The water-soluble drugs such as cefadroxil, cephradine, 4-aminoantipyrine, and antipyrine were selected and entrapped separately in the inner aqueous phase of W/O/W multiple emulsion. In consideration of parenteral administration, pH 7.4 phosphate buffered saline was used in both inner and outer aqueous phases. Moreover, these multiple emulsions could be significantly stable for a month at room temperature by the addition of hydrophilic polymer like gelatin and of amino acid like lysine to the inner aqueous phase.

Pharmacokinetics of cefroxadine after infusion to healthy volunteers

The pharmacokinetics of cefroxadine in healthy human volunteers was studied in plasma and urine, after an infusion administration of 1 g of this drug for 0.5 h. Blood and urine samples were microbiologically quantified by diffusion on solid gelose using Bacillus Subtilis ATCC 6633 as the test organism. Plasma and urine profiles were fitted to a reduced two-compartment model not having inactivating biotransformation as a route of elimination. The parameters of distribution for this model show a rapid disposition (t1/2 alpha = 0.28 h) and an average volume of the central compartment of 0.15 +/- 0.04 l/kg (range 0.20-0.09). The dominant terminal half-life (beta-phase) was 1.17 +/- 0.26 h (range 0.90-1.67). The total body volume 0.41 +/- 0.09 l/kg (range 0.30-0.52) indicates that there is no diffusion of the antibiotic into intracellular fluids of poorly perfused tissues due to its high elimination rate.

[Lyell's syndrome--possibly drug-induced epidermal necrolysis in a 7-year-old boy]

In a 7-year-old child Lyell's syndrome was observed with extensive bullous epidermal necrolysis with a very severe clinical course. The disease could have been explained as a toxic-allergic reaction to sefril and aspirin taken for pharyngitis.

Pharmacokinetics of cephradine administered intravenously and orally to young and elderly subjects

The pharmacokinetics of IV and oral cephradine in healthy young male and female volunteers (ages 19 to 25, n = 10) were compared to those of older individuals (ages 65 to 81, n = 9). Subjects received 1 gram of cephradine by a 5-minute intravenous (IV) infusion followed the next day by a 1-gram oral dose. Serial serum and urine samples collected over a period of 12 hours after the dose were analyzed for cephradine concentration by a microbiologic assay. After IV administration, mean serum cephradine concentrations in the elderly group were significantly higher at both 6 hours (1.52 +/- 0.41 mcg/mL) and 8 hours (0.73 +/- 0.22 mcg/mL) than in the young group at 6 hours (0.43 +/- 0.11 mcg/mL). Total systemic clearance was significantly lower (2.64 +/- 0.34 vs. 4.81 +/- 0.59 ml/min/kg) and the elimination half-life was significantly longer (1.71 +/- 0.20 vs 1.12 +/- 0.13 hours) in the elderly group (P = .0001). Systemic cephradine clearance correlated positively with creatinine clearance (r2 = 0.34, P = .0110) and negatively with age (r2 = 0.79, P = .0052). The mean volume of distribution was not significantly different between the two groups. Mean renal clearance was significantly lower in the elderly group (P = .0001), but more than 80% of the dose was excreted in the urine within 6 hours in both groups. After oral administration, the mean peak concentration and time to peak concentration did not differ between groups. The relative oral bioavailability was approximately 94% in both groups. The mean serum concentrations in the elderly were higher at both 6 and 8 hours than in the young group at 6 hours. There were no differences in pharmacokinetic parameters between male and female subjects. Because of reduced cephradine clearance secondary to an age-related decline in renal function, administration of cephradine every 8 hours, rather than every 6 hours, may be sufficient in elderly patients.

Cephradine (Velosef) penetration of mandibular bone

The concentration of cephradine in serum and mandibular bone was assayed in 28 patients undergoing 3rd molar surgery following a single 1 g intravenous injection. Serum and cortical bone samples taken simultaneously, contained mean cephradine concentrations of 42.11 micrograms/ml and 2.61 micrograms/g respectively. These results, when compared with those reported for other bony sites including the femoral head and knee, show a reduced bone penetration with a bone-to-serum ratio of approximately 0.06:1.

In-vitro evaluation of a new oral cephalosporin, cefroxadine (CGP 9000)

The in vitro activity of cefroxadine was studied and found to be at least comparable to that previously reported for cefalexin and cefradine. The activity of cefroxadine was superior to that of amoxicillin against tested isolates. Time-killing studies showed that the addition of 4 X minimum inhibitory concentration (MIC) of cefroxadine to growing cultures reduced viable counts by 4 log units within a 3 h incubation. A diffusion test with a 30 microgram cefroxadine disk produced acceptable interpretive results with tentative zone size breakpoints of less than or equal to 14 mm for resistance and greater than or equal to 17 mm for susceptibility.

Toxic shock syndrome following diagnostic peritoneal lavage

We report the case of a 15-year-old girl who developed high fever, syncope, abdominal pain, nausea and vomiting, myalgia, pharyngitis, and a desquamating rash eight days after a diagnostic peritoneal lavage. The diagnostic peritoneal lavage wound was erythematous and tender. Incision of the site yielded 10 mL of exudate that cultured Staphylococcus aureus. The patient was treated with a first-generation cephalosporin and recovered without sequelae. To our knowledge, this is the first reported case of toxic shock syndrome following diagnostic peritoneal lavage.

Short-term cephradine prophylaxis in elective transurethral prostatectomy

A prospective randomized trial was conducted to assess the value of short-term antibiotic prophylaxis in elective transurethral resection of the prostate. Two hundred patients were randomized to receive 1.5g cephradine intramuscularly preoperatively and 1g cephradine orally before removal of the urethral catheter or to receive no antibiotic prophylaxis. Fifty-eight patients were excluded because of occult neoplasm or protocol violation. There was no difference in time to removal of catheter, incidence of pyrexial episodes, length of hospital stay or minor complication rate between the two groups. We conclude that a short-term antibiotic regime is of no value in the elective patient with sterile urine.

The penetration of antibiotics into the normal intervertebral disc

The role of antibiotics in the treatment of disc-space infection is controversial. This study assessed the tissue penetration of flucloxacillin and cephradine into the normal intervertebral disc after intravenous administration of a bolus dose of antibiotic. Twenty-five discs were removed from 12 adolescent patients having anterior spinal surgery to correct scoliosis; antibiotic had been administered between 30 minutes and four hours before operation. Despite high blood levels, no antibiotic could be detected by bioassay or by high-pressure liquid chromatography (h.p.l.c.) in any of the specimens from the nucleus pulposus or the annulus fibrosus.

One and two doses of cephradine in the prophylaxis of experimental streptococcal endocarditis

The efficacy of cephradine in the prophylaxis of rabbit Streptococcus sanguis endocarditis was investigated. Three days after cardiac catheterization and prior to challenge with S. sanguis, rabbits received either 1000 mg/kg (ten animals) or 500 mg/kg cephradine intramuscularly. Infective endocarditis was prevented in only 30% of the animals. The addition of a second dose of cephradine (100 mg/kg) 8 h after an initial dose of 400 mg/kg did not prevent streptococcal endocarditis in 80% of animals tested. In one or two dose regimens cephradine was found to be inferior to a single 400 mg/kg prophylactic dose of amoxycillin. Cephradine is not recommended for prophylaxis against streptococcal endocarditis.

Clinical pharmacokinetics of five oral cephalosporins in calves

The minimal inhibitory concentrations (MIC) of cephalexin, cephradine, cefaclor, cefatrizine and cefadroxil for Salmonella species, Escherichia coli and Pasteurella multocida isolated previously from young calves were determined. The MIC90 values for cephalexin, cephradine and cefadroxil ranged between 3.12 micrograms ml-1 and 12.5 micrograms ml-1, whereas those of cefatrizine and cefaclor were 3.12 micrograms ml-1 and 0.78 microgram ml-1, respectively. Each drug was administered intravenously and orally to groups of pre-ruminating calves and orally to early ruminating calves. Although the pharmacokinetic characteristics of the drugs after intravenous injection were similar to other beta-lactam antibiotics, significant differences between the cephalosporins examined were found in respect of certain kinetic parameters. The drugs showed rapid absorption into the systemic circulation after oral administration to pre-ruminating calves but the elimination half-life values (t1/2 beta) varied between three hours (cefaclor and cefadroxil) and nine hours (cefatrizine). The bioavailability of the drugs was about 35 per cent of the administered dose. Co-administration of probenecid with each antibiotic caused a twofold or greater increase in peak serum drug concentrations (Cmax) but the effect on t1/2 beta was variable. Cephalexin, cephradine and cefaclor given to the ruminating calves resulted in very low serum or plasma concentrations and their use should be restricted to younger calves. Cefadroxil was found to give the highest serum concentrations in this age group but had significantly lower bioavailability when compared with the unweaned calves. Provisional oral dosage regimens were computed for each cephalosporin on the basis of the MIC data and the kinetic parameters derived from intravenous and oral drug administration.

[A clinical study on cefroxadine in the treatment and recurrence of acute uncomplicated cystitis]

Cefroxadine (CXD) was administered to patients with acute uncomplicated cystitis (AUC) in a dose of 250 mg t.i.d. for 3-7 days. The patients were divided into 2 groups (less than 70 and greater than or equal to 70 years old) and clinical efficacy and incidents of recurrence were assessed. 1. Out of 83 patients treated, clinical efficacy was evaluated in 62 patients including 10 elder patients on the 3rd day and in 47 patients including 9 elder patients on the 7th day. In both groups clinical efficacy rates were 100% on the 3rd and 7th day. 2. Among 24 patients including 7 elder patients, who showed excellent response on the 7th day, recurrence was examined on the 14th day. The recurrence rate was 0% by the criteria proposed by the UTI committee in Japan. However, two patients (under 70 years of age) among them were considered as positive for recurrence by doctors in charge. Consequently, in both aged groups CXD showed excellent results in the treatment of AUC.

Comparison of the pharmacokinetics of cephradine and cefazolin in pregnant and non-pregnant women

The pharmacokinetics of cephradine, a cephalosporin with a low degree of protein binding, was studied in 12 women after oral and intravenous administration of the drug during and after pregnancy. Six of the 12 women also received a cephalosporin with a high degree of protein binding, cefazolin, intravenously during and after pregnancy. For both drugs most pharmacokinetic parameters were altered in pregnancy. The area under the plasma concentration-time curve (AUC) following intravenous administration was smaller for both drugs during as compared to after pregnancy (mean change 39% for cephradine and 31% for cefazolin). Half-lives of both drugs were significantly shorter during compared with after pregnancy (mean change 26% for cephradine and 35% for cefazolin). Consequently, total body clearance was increased during pregnancy. A significant negative correlation between length of gestation and total clearance per kg bodyweight was seen for cephradine. The bioavailability of oral cephradine did not differ significantly during compared with after pregnancy. It is concluded that the dosage of both cefazolin and cephradine should be increased when treating infections in pregnant women in order to obtain the same antibacterial effect as when treating non-pregnant women.

Bone levels of cephradine and cefuroxime after intravenous administration in patients undergoing total hip replacement

A randomised, comparative study is reported of single intravenous doses of cephradine 2 g or cefuroxime 1.5 g given as prophylactic cover for total hip replacements in 40 patients. The serum and bone levels of cephalosporin achieved were higher in the cephradine treated group in proportion to the higher dose employed. Both agents provided adequate bone levels on average, cephradine 25.34 mcg/g, cefuroxime 17.39 mcg/g, although bone penetration was more variable with cefuroxime.

[Influence of cefroxadine dry syrup on intestinal bacterial flora]

Influence of cefroxadine (CXD) dry syrup on intestinal bacterial flora was studied in mice infected with 4 species of bacteria, namely, Escherichia coli, Enterococcus faecalis, Bacteroides fragilis and Bifidobacterium breve, and in pediatric patients having infections in the respiratory tract and cutaneous/soft tissues. The results were summarized as follows: CXD dry syrup was administered for 5 consecutive days to mice infected with the 4 species. No considerable changes were observed in levels of bacteria in the feces and in different parts of digestive tracts. Eleven pediatric patients were orally administered with 30-54 mg/kg of CXD dry syrup a day for 7-15 consecutive days. Symptom of diarrhea was noted in 2 patients. Dominant species of the intestinal flora such as E. coli, Bifidobacterium, and Bacteroides sometimes decreased in patients treated with CXD dry syrup. In general, however, decreases in numbers of these bacteria were insignificant. Changes of intestinal flora in patients treated with CXD dry syrup were apparently smaller than those treated with ampicillin and were similar to those treated with cephalexin or amoxicillin.

Effect of inflammation on antibiotic penetration into the anterior segment of the rat eye

Bacterial infections were established in the right cornea of rats. Animals infected with Staphylococcus aureus were given cephradine intravenously (IV) (40 mg/kg) or topically (50 mg/ml) to both eyes. Animals infected with Pseudomonas aeruginosa were given gentamicin sulfate IV (40 mg/kg) or topically (10 mg/ml). Antibiotic concentrations in cornea and aqueous humor were measured for 4 hrs following dosing using bioassay and radioimmunoassay. In general, infection significantly increased the concentrations obtained soon after dosing. Topically applied cephradine passed through infected eyes more quickly than through normal eyes. Of the pharmacokinetic parameters derived, the permeability of the corneal epithelium to gentamicin in the rat more closely agrees with reported human values than does the rabbit, while the coefficient of elimination from aqueous in the rat is considerably greater than that for either humans or rabbits. This suggests that there are both advantages and disadvantages in using the rat for therapeutic studies of ocular disease.

Are preoperative antibiotics helpful in abdominal hysterectomy?

An open, randomized study to compare the effectiveness of triple-dose cefoxitin with the effectiveness of cephradine-tinidazole and with the result of nontreatment in patients undergoing abdominal hysterectomy was conducted from July 1983 to July 1984. One hundred ninety-nine patients were enrolled: 66 untreated control patients, 69 patients in the cephradine-tinidazole--treated group, and 64 patients in the cefoxitin-treated group. No significant differences were present in relation to age, pathologic condition, length of operation, blood loss, or length of hospital stay. That patients in both treatment groups had a lower incidence of postoperative febrile morbidity was not statistically significant.

The cephalosporin antibiotics in pediatric therapy

The cephalosporins have been available for clinical use for nearly 20 years and a large number is presently marketed, including drugs with a wide range of different pharmacokinetic and microbiologic properties. While some of these agents have certain specific uses in which they excel, the cephalosporins have not replaced older antibiotics but do provide the physician with a broader range of choices for the treatment of many infections, allowing greater individualization of therapy.

CAPD peritonitis: a prospective randomized trial of oral versus intraperitoneal treatment with cephradine

In a prospective randomized clinical trial 84 peritonitis episodes were treated with cephradine, either orally or intraperitoneally. No difference in treatment outcome between both groups could be demonstrated. In episodes caused by susceptible micro-organisms a good response was seen in 82% in the oral and 82% in the intraperitoneal groups. These clinical findings were supported by the demonstration of adequate cephradine concentrations in serum and dialysate after oral as well as after intraperitoneal administration. Altogether cephradine was given orally or intraperitoneally in 88 episodes of peritonitis as drug of first choice. In 52 a complete cure was obtained, in 36 another antibiotic was subsequently needed as soon as bacterial susceptibility was known. No patient deteriorated appreciably during the delay between the start of cephradine and the switch to another antibiotic. Of the 36 episodes 14, caused by methicillin-resistant Staphylococcus epidermidis, responded well initially to cephradine but relapsed later. Change to another antibiotic effected a complete recovery in all 14 cases. Of the remaining 22 episodes, 14 were cured by the other antibiotic, in eight the catheter had to be removed. Aminoglycosides could be avoided except for ten of the episodes. During peritonitis CAPD was continued, in 71% of the cases on an outpatient basis. Mortality due to peritonitis was absent. We conclude that oral cephradine can be used as drug of first choice in the initial treatment of CAPD peritonitis, because a good initial response was obtained in 66 (52 + 14) i.e. 75% of 88 episodes. However, complete cure by cephradine alone was achieved in only 60%.(ABSTRACT TRUNCATED AT 250 WORDS)