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PubMed1991

[Clinical effect of the combined use of aztreonam, amikacin and clindamycin in infectious disease in obstetrics and gynecology].

Clinical effects of combined use of aztreonam (AZT), amikacin (AMK) and clindamycin (CLDM) in 46 cases with infectious diseases in obstetrics and gynecology were retrospectively studied in 2 groups, and the following results were obtained. 1. No significant difference in efficacy rates was noted between AZT plus CLDM treated group (n = 25) and AMK plus CLDM treated group (n = 21) (96.0% vs. 95.2%), while rate of excellent efficacy was slightly higher in AZT plus CLDM group than AMK plus CLDM group (24.0% vs. 14.3%). 2. No significant difference in bacteriological clinical effects was also noted between the 2 groups, while bacteriological eradication rate was higher in the AZT plus CLDM group than in the other group (76.2% vs. 50.0%), and the difference was particularly clear in the eradication rates of aerobic, Gram-negative bacteria (88.9% vs. 30.0%). 3. Subjective and objective side effects, and abnormalities of clinical test results were not found in either group.

Adult↗

PubMed1991

[Combined antibacterial activity of aztreonam and clindamycin against clinically isolated strains].

It has been reported in some studies that the combination of aztreonam (AZT) and clindamycin (CLDM) have high clinical effectiveness in the treatment of intractable infections. We, therefore, studied combined in vitro antibacterial activity of these 2 compounds using many freshly isolated strains. 1. AZT and CLDM in combination had synergistic effects on Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Haemophilus influenzae, which are sensitive or quasi-sensitive to CLDM, in the presence of CLDM at MIC or sub-MIC. 2. For Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Enterobacter cloacae, Serratia marcescens, and Pseudomonas aeruginosa, which are not sensitive to CLDM, the 2 drugs in combination showed synergistic effects on some species and additive or slightly additive effects on most species in the presence of CLDM at those concentrations which are usually maintained in blood. 3. The 2 drugs showed no antagonism.

Aztreonam↗

PubMed1991

[Dose calibration of aztreonam in pediatric patients by means of pharmacokinetic analysis].

One of the current pharmacological problems with antibiotics is possible overdose among children of 7 years of age and older, when their dose was calculated on a per kg basis. In order to evaluate the difficulties, a pharmacokinetic analysis of aztreonam (AZT), which is a monocyclic beta-lactam antimicrobial agent, was undertaken in 2 groups consisting of 5 children of ages 1-6 and 5 older children of 7-15. Data from the younger children were fitted both to one- and two-compartment models while those from the older age group perfectly were fitted to a two-compartment model. Using these fitted curve, a simulation dose study was carried out in order to see if we can find a clue for a better dose calibration for the older group of children. The results suggested that the dose of AZT in per kg basis for the older children can be reduced to 60% levels of the younger, that is, 60 mg/kg for the older in contrast to 100 mg/kg for the younger.

Age Factors↗

PubMed1991

[Combination antibacterial effects between aztreonam and eight other antibiotics].

In vitro interactions between aztreonam (AZT) and 8 other antibiotics were studied using the agar dilution checkerboard technique against 88 clinical isolates of Escherichia coli, Proteus vulgaris, Serratia marcescens and Pseudomonas aeruginosa. Combinations of AZT with 8 other antibiotics were generally additive or indifferent. Synergism was occasionally seen against S. marcescens or P. aeruginosa with AZT plus isepamicin (ISP). Antagonism was observed only between AZT and latamoxef against P. vulgaris. In a phase-contrast microscopic study, synergistic effects between AZT and aspoxicillin or ISP were confirmed against E. coli 177 and P. aeruginosa 15846. AZT in combination with ISP demonstrated a synergy against experimental urinary tract infection in mice caused by P. aeruginosa 15846. We believe that combinations of several antibiotics with AZT should be considered for initial therapy of infections because synergism and additive action were observed and antagonism was rarely found in our study.

Amoxicillin↗

PubMed1990

[Combination therapy with aztreonam and clindamycin on severe infections accompanying neutropenic patients with hematological disorders].

We studied effectiveness and safety of combination therapy of aztreonam (AZT) (2-6 g/day) and clindamycin (CLDM) (1,200-2,400 mg/day) on severe infections in neutropenic patients with hematological diseases. We administered AZT and CLDM to 250 consecutive patients and analyzed the results of a total of 212 cases for evaluation except 38 cases of exclusions and dropouts. Hematological malignancies constituted the dominating underlying diseases which represented 90.6% of all underlying diseases. The overall clinical efficacy of the combination therapy with AZT and CLDM was 65.6% and the following results were obtained for different categories: sepsis, 64.7%; suspected sepsis, 66.4%; and pneumonia 54.5%. Even severe patients with less than 100/microliters of neutrophil counts showed good responses with an efficacy rate at 57.4%. Side effects were observed in only 7 cases (2.8%). We concluded that the combination therapy with AZT and CLDM would be useful as empiric therapy against various infections in febrile neutropenic patients with hematological diseases.

Adult↗

PubMed1990

[Clinical evaluation of aztreonam for infections accompanying febrile neutropenic children with hematologic disorders and solid tumors. A cooperative study].

One hundred four children with infection accompanying hematologic disorders and solid tumors were treated with aztreonam (AZT) (120-150 mg/kg), either alone or in combination with one of the following drugs; cefmetazole (CMZ) (120-150 mg/kg), piperacillin (PIPC) (120-150 mg/kg), or amikacin (AMK) (5-10 mg/kg). The overall efficacy rate was 69.2%. Efficacy rates by regimen were as follows: AZT alone was 63.2%, AZT plus CMZ was 73.6%, AZT plus PIPC was 74.1% and AZT plus AMK was 20.0%. Efficacy rates in different types of infections were 53.2% for sepsis and suspected sepsis, 78.9% for pneumonia and respiratory tract infection, 93.1% for fever of undetermined origin and 55.6% for other infections. The efficacy rate was 71.3% in 94 patients in whom causative organisms were not identified and 50.0% in 10 patients in whom causative organisms were identified. Most of infections in which causative organisms were identified were caused by Gram-negative pathogens. The response rate among infections caused by Gram-negative bacilli was 50.0%. A combination of AZT and CMZ or PIPC was effective in 3 (100.0%) out of 3 patients in whom Escherichia coli was the causative organism. Efficacies classified according to different neutrophil counts were 59.3% for less than or equal to 100/microliters, 78.6% for 101-500/microliters and 82.4% for greater than or equal to 501/microliters. No significant adverse reactions were observed. These results indicated that combination of AZT and 2nd generation cephalosporins or penicillins were well tolerated and effective for infections complicated with accompanying hematologic disorders and solid tumors.

Adolescent↗

PubMedDate not supplied

[Aztreonam and clindamycin in short-term antibiotic prophylaxis in colorectal surgery: results of a multicenter studies].

The Authors studied the effects of a short-term prophylaxis (Aztreonam + Clindamycin) administered to 259 patients operated on for colo-rectal diseases. Thirteen wound sepsis (5.15%) and 49 different infections (19.44%) occurred in this group of patients. The study confirms the link between P.N.I. greater than 50 and the incidence of wound infections. The incidence of urogenital sepsis was correlated with the catheterization period (greater than 6 days), operative time (greater than 200 min.), hospitalization (greater than 12 days) and age (greater than 70 years). General tolerance to the antibiotics was good.

Adolescent↗

PubMed1990

[Studies on aztreonam in the perinatal period].

Pharmacokinetic, bacteriological and clinical studies on aztreonam (AZT) in the perinatal period were carried out with the following summary of the results. Antibacterial effects of AZT on bacterial growth of Escherichia coli (MIC 12.5 micrograms/ml) and Pseudomonas aeruginosa (MIC 50 micrograms/ml) in amniotic fluid were determined and it was found that the activity of AZT is enhanced in amniotic fluid. AZT rapidly penetrated into tissues and sera of pregnant women upon intravenous (i.v.) injection and its maternal serum concentrations reached their peak levels shortly after the injection. Placental penetration of AZT to the fetus was good and, after single i.v. injection of 1 g, the concentrations of AZT in the umbilical cord serum and amniotic fluid exceeded MICs against major Gram-negative bacilli. These results indicate that single i.v. injection of AZT 1 g twice a day is effective for the treatment and prophylaxis of perinatal infections. Injection of AZT for the treatment of puerperal infections showed excellent clinical effectiveness with 100% eradication of aerobic Gram-negative rods. No side-effect was observed in any case. All of the results suggested clinical usefulness of AZT in the perinatal period.

Adult↗

PubMed1990

[The use of endobronchial aztreonam in the treatment of bronchiectatic suppuration].

The authors submitted 8 patients with bronchiectasis to endobronchial therapy with Aztreonam 2 gr twice a week for 4 weeks after endobronchial lavage with sodium chloride solution. They observed a definite clinical and radiological improvement and a stabilized condition of the disease was observed. No hepatic or renal toxicity was detected.

Adult↗

PubMed1990

[Pharmacokinetic, bacteriological and clinical studies on aztreonam in neonates].

Pharmacokinetic, bacteriological and clinical studies on aztreonam (AZT) were performed in neonates. The results obtained are summarized as follows. 1. Plasma levels and urinary excretion of AZT were determined in 18 neonates with ages between 1 and 30 days (gestation periods were 36 to 40 weeks and birth weights were 1,890 to 4,300 g) and in 2 infants with 54 and 60 days of age (gestation periods were 36 and 40 weeks, and birth weights were 2,300 and 3,300 g, respectively) upon one-shot intravenous injection of AZT 10 mg/kg (7 cases) or 20 mg/kg (11 cases) to the 18 neonates and 20 mg/kg to the 2 infants. Ampicillin (ABPC) 25 mg/kg was simultaneously injected to 5 cases of the neonates given AZT 20 mg/kg by one-shot intravenous injection and plasma concentrations of ABPC in these 5 cases were also studied. Plasma concentrations in neonates at 0.5 hour after intravenous injection of AZT 10 mg/kg were 11.5 to 27.6 micrograms/ml (average 20.3 +/- 5.5 micrograms/ml) and decreased with half-lives of 2.72 to 5.70 hours (average 3.81 +/- 1.28 hours), and the plasma levels at 8 hours after administration were 3.3 to 8.7 micrograms/ml (average 5.8 +/- 2.5 micrograms/ml). In the cases given AZT at 20 mg/kg, plasma levels at 0.5 hour were 12.4 to 48.8 micrograms/ml (average 35.9 +/- 11.6 micrograms/ml) and decreased with half-lives of 1.69 to 4.14 hours (average 2.94 +/- 0.76 hours) and AZT levels at 8 hours were 1.1 to 10.6 micrograms/ml (average 5.6 +/- 3.6 micrograms/ml). Urinary recovery rates in the first 8 hours after intravenous injection of the 10 mg/kg group were 15.5 to 61.9% (average 37.8 +/- 21.8%) and 16.3 to 62.2% (average 43.5 +/- 16.2%) for the 20 mg/kg group. Plasma concentrations in infants after administration of AZT 20 mg/kg were 33.0 to 35.6 micrograms/ml (average 34.3 +/- 1.8 micrograms/ml) at 0.5 hour and decreased with half-lives of 1.76 to 3.77 hours (average 2.77 +/- 1.42 hours) and AZT plasma levels at 8 hours were 1.4 to 5.8 micrograms/ml (average 3.6 +/- 3.1 micrograms/ml). Urinary recovery rates were 35.4 to 64.8% (average 50.1 +/- 20.8%). These results suggested that AZT shows a dose-dependent, high plasma concentration even in the neonatal period, as well as good urinary excretion from an early stage of the administration.(ABSTRACT TRUNCATED AT 400 WORDS)

Ampicillin↗

PubMed1990

[Pharmacokinetic study of aztreonam transfer from mother to fetus].

Aztreonam (AZT) was administered to 73 cases and its usefulness and safety were evaluated upon review of the transfer of the drug into maternal blood, umbilical cord blood and amniotic fluid. The result obtained are summarized as follows. 1. AZT was intravenously administered by single injection to obtain actual data. Based on the data, theoretical changes of drug concentrations in serum in mother were reviewed according to the lapse of time. Drug concentration in maternal blood showed its peak immediately after administration and gradually decreased thereafter. Umbilical cord blood concentration showed a lower peak, which was reached with a slight delay to the Tmax for maternal blood concentration, then decreased. The decrease, however, was more moderate than the decrease in maternal blood concentration and, according to the theoretical values, umbilical cord blood concentration was higher than maternal blood concentration at 2.23 or 2.24 hours after administration. AZT concentrations in amniotic fluid slowly increased after administration and were higher than umbilical cord blood concentrations at 1.68, 1.73 hours after administration, higher than maternal blood concentrations at 1.82, 1.85 hours after administration, and they reached their peak somewhat later. Subsequently, high concentrations of AZT in amniotic fluid were maintained for a long time. The result suggests that AZT is useful for prophylaxis and treatment of amniotic fluid infections. 2. Theoretical values were analyzed by applying two-compartment model and three-compartment model to the actually-measured values, and each parameter was compared. T 1/2 of AZT concentrations in maternal blood and in umbilical cord were 1.29 hours, 1.29 hours, 2.14 hours, 2.00 hours; Cmax 187.09 micrograms/ml, 184.15 micrograms/ml, 30.63 micrograms/ml, 30.66 micrograms/ml and AUC 153.25 micrograms.hr/ml, 153.40 micrograms.hr/ml, 123.19 micrograms.hr/ml, 123.09 micrograms.hr/ml respectively showing approximate values. Cmax values of AZT in amniotic fluid were 47.08 micrograms/ml, 47.74 micrograms/ml; AUC 948.03 micrograms.hr/ml, 1,028.70 micrograms.hr/ml also showing approximate values. However, volume of distribution of umbilical cord blood and amniotic fluid showed a difference according to compartment model. 3. It was considered from the above results that application of only two-compartment open model would make analysis possible when only T 1/2, Cmax and AUC values must be measured for mother-to-fetal transfer of a drug. 4. No subjective and objective side effects nor abnormal laboratory values were observed in any of these cases (both mothers and fetuses).

Amniotic Fluid↗

PubMed1990

[Pharmacokinetics of aztreonam on hemodialysis].

We studied the pharmacokinetics of aztreonam (AZT) in 6 patients with renal insufficiencies during nonhemodialysis and hemodialysis. After intravenous injection of 1 g AZT, it was found that serum AZT concentrations during hemodialysis were different from those during nonhemodialysis and serum half-lives (T 1/2 beta) were 3.44 hours and 16.97 hours, respectively. AZT clearance changed from 0.762 L/hr during hemodialysis to 3.360 L/hr during nonhemodialysis. These findings suggest that hemodialysis patients should receive the standard dose of AZT as a loading dose, followed by one-half the loading dose per day and receive a supplemental dose equal to half their usual maintenance dose after each dialysis session.

Aged↗

PubMed1990

[Clinical and pharmacokinetic evaluation of aztreonam in neonates].

Nine neonates were treated with aztreonam (AZT) and its clinical efficacy and side effects were evaluated. Six of the patients were treated with a combination of AZT and ampicillin. Ages of the patients ranged from 0 to 24 days, and their body weights ranged from 2,290 to 4,260 g. Doses of AZT ranged 18.8 to 23.7 mg/kg every 8 to 12 hours for 3 to 7 days. Three patients with infections including urinary tract infection, cervical abscess, and suspicion of sepsis, appeared to respond to the treatment of AZT alone. Among them, clinical results were excellent in 1, good in 2 patients. Those patients subjected to the combination therapy showed excellent response in 1 and good in 5. The drug was well tolerated, but 1 had diarrhea. The pharmacokinetics of AZT was studied in 9 patients. Their ages ranged from 0 to 30 days, and body weights ranged from 2,000 to 4,000 g. Serum concentrations of AZT were 27.2 to 48.3 micrograms/ml at 1 hour after single 20 mg/kg intravenous bolus injection, and the levels were 3.4 to 15.5 micrograms/ml at 6 hours in 5 infants heavier than 2,500 g. Elimination half-lives of AZT ranged from 1.57 to 3.72 hours (mean 2.72 hours). Serum concentrations of AZT were 21.6 to 41.8 micrograms/ml at 1 hour after single 20 mg/kg intravenous bolus injection, and the levels were 10.2 to 17.0 micrograms/ml at 6 hours in 3 infants lighter than 2,500 g. The elimination half-lives of AZT were 3.63 to 4.86 hours (mean 4.31 hours).(ABSTRACT TRUNCATED AT 250 WORDS)

Ampicillin↗

PubMed1990

[Clinical and pharmacokinetic studies on aztreonam in neonates].

Clinical and pharmacokinetic studies on aztreonam (AZT) were performed in neonates. The results are summarized as follows: A total of 6 cases consisting of 5 mature and 1 low-birth-weight infants was clinically evaluated. AZT 20 mg/kg was administered 2-3 times daily, via 1 hour intravenous drip infusion for 6-21 days. Concomitantly, vancomycin (VCM) 15 mg/kg was administered to 1 case 3 times daily, via 1 hour intravenous drip infusion for 3 days and ampicillin (ABPC) 20-50 mg/kg to 3 cases 3 time daily via 30 minutes intravenous drip infusion for 2-6 days. Of the 6 bacterial infection cases (1 with sepsis and purulent meningitis, 2 with sepsis, 2 with urinary tract infection and 1 with perirectal abscess), clinical effects of AZT were evaluated in 4 cases (2 each with sepsis and urinary tract infection) as "excellent" in all the cases. All of the causative organisms (Escherichia coli in 3 and Enterobacter cloacae in 1) were eradicated by the treatment with AZT. Neither clinical side effect nor abnormal laboratory test value caused by AZT was observed. MICs of AZT against 10 clinical isolates (Staphylococcus aureus 1, E. coli 4, Klebsiella pneumoniae 1, E. cloacae 1, Haemophilus influenzae 1 and Pseudomonas aeruginosa 2) from neonatal patients with bacterial infections were examined. As results, AZT showed very good antibacterial activity comparable or even superior to cefoperazone, cefotaxime, latamoxef; however, the activity against P. aeruginosa was inferior to imipenem.(ABSTRACT TRUNCATED AT 250 WORDS)

Ampicillin↗

PubMed1990

[Pharmacokinetics and clinical safety of aztreonam in neonates].

Clinical pharmacology and safety of aztreonam (AZT) in the neonatal period were investigated. The results obtained are summarized as follows. 1. Serum concentrations of AZT at 30 minutes after administration of 10 mg/kg were 22.1-32.2 micrograms/ml and those of 20 mg/kg 22.5-75.9 micrograms/ml. 2. Serum half-lives of AZT were 3.5-6.6 hours in 0-3 day-old neonates, and 2.0-4.0 hours in neonates 4 day-old or older. 3. A dose response was evident between the 10 mg/kg administration group and the 20 mg/kg group. 4. Urinary recovery rates of AZT in the first 6 hours after administration ranged between 17.8 and 69.9%. 5. No clinical side effects were observed in the administration of AZT alone (6 cases), or in combination with ampicillin (9 cases). Thrombocytosis was observed in 1 case as an abnormal laboratory finding, but it returned to normal within 1 week after the completion of AZT administration. 6. AZT had a potent antimicrobial activity against Gram-negative aerobes and hardly induced beta-lactamase. Furthermore, side effects were not observed in this study. Therefore, AZT is considered to be useful for the treatment of urinary tract infections and other serious infections caused by Gram-negative pathogens even in the neonatal period.

Age Factors↗

PubMed1990

[Pharmacokinetic and clinical studies on aztreonam in neonates and premature infants].

Aztreonam (AZT) was studied for its pharmacokinetics, clinical effect and effect on intestinal bacterial flora in neonates, and the results obtained are summarized as follows: 1. Serum concentrations of AZT upon intravenous administration of 20 mg/kg were 38.6 micrograms/ml in 30 minutes, 30.6 micrograms/ml in 1 hour and 13.6 micrograms/ml in 6 hours. The T 1/2 was 3.73 hours. Ampicillin (ABPC) 25 mg/kg was concurrently used with AZT in 2 cases and serum concentrations of AZT in these 2 cases were 40.3 and 36.9 micrograms/ml in 30 minutes, 35.7 and 32.6 micrograms/ml in 1 hour, and 13.1 and 10.2 micrograms/ml in 6 hours, respectively. T 1/2's were 3.32 and 2.91 hours, respectively, and no interaction between the 2 drugs was observed. 2. AZT was administered to 21 neonates between 0 and 83 days of age and ABPC was concurrently administered to 18 of the cases. Clinical evaluation was made in 14 cases, where AZT was remarkably effective in 7 cases, effective in 6 cases and not effective in 1 case. Of the 21 cases, 1 case of diarrhea, 1 case each of eosinophilia, an increase in platelets, an increase in platelets and an elevation of GOT and a decrease in platelets were recorded. 3. With respect to effects of AZT on intestinal bacterial flora, fecal concentrations of AZT upon its single administration to 2 cases were low suggesting, there was little effect on the intestinal flora. Some effect on anaerobes, however, was recognized in 4 cases in which ABPC was concurrently used.

Ampicillin↗

PubMed1990

[Pharmacokinetic and clinical evaluation of aztreonam in neonates and premature infants].

In order to study serum concentration and urinary concentration (urinary recovery rate) of aztreonam (AZT), AZT was administered via intravenous bolus injection at dose levels of 10 mg/kg, 20 mg/kg and 50 mg/kg to 7 cases of 4 to 26 days old mature or premature infants nearing cure-stage of various bacterial infections upon the treatment with AZT. Clinical evaluation was made in 19 cases with therapy with AZT alone and 13 cases with combination therapy with AZT + ampicillin (ABPC), with a total of 32 cases. The former group included 10 males and 9 females of 0 to 43 days of age and the latter group included 7 males and 6 females of 6 to 41 days of age. All the cases treated with AZT alone including 5 cases for prophylaxis were evaluable. In the 13 combination therapy cases, however, the effect of AZT was evaluable only in 3 cases excluding the cases in which ABPC-susceptible bacteria were the culprits. 1. Changes in serum concentrations and urinary recovery of AZT. Pharmacokinetics of AZT in serum was examined in 5 matured infants at dose levels of 10 mg/kg in 2 cases and 20 mg/kg in 3 cases. Highest levels were observed with the first sampling at 30 minutes after administration in all the cases with values of 29.1 micrograms/ml with 10 mg/kg dose, and 37.8 micrograms/ml and 55.5 micrograms/ml with 20 mg/kg dose in in cases with ages between 4 and 7 days and 1 case with age above 8 days, respectively. Half-life (T 1/2) values were 3.42, 3.05 and 1.58 hours, respectively for the above three groups of patients. As is described here, the T 1/2 value in the infant with age above 8 days was considerably shorter than the T 1/2 values in infants of younger day-ages. Urinary recovery rates of administered AZT were between 10.4 and 52.6%, showing a large individual diversity. In addition to the above cases, one premature infant was administered with AZT (the dose level: 50 mg/kg) and examined for pharmacokinetic parameters at day-ages of 11 days and 19 days. Serum levels of AZT examined were the highest at 30 minutes after dosage (the first sampling) and were 106.8 micrograms/ml at 11 days of age, and 90.4 micrograms/ml at 19 days of age. Serum levels decreased to 16.2 and 9.6 micrograms/ml, respectively, in 8 hours after dosage, at ages of 11 and 19 days. T 1/2 values were 2.62 and 2.35 hours, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Ampicillin↗

PubMed1990

[Studies of aztreonam in neonates].

Absorption and excretion of aztreonam (AZT) in neonates were studied and its clinical evaluation in 10 cases of neonates was performed using 1 hour intravenous drip infusion. 1. Serum concentrations of AZT in 7 neonates younger than 11 days of age were lower than those in infants. 2. Serum concentrations of AZT in 5 neonates given 20 mg/kg reached their peaks at the end of intravenous drip infusion with an average value of 45.8 +/- 10.41 micrograms/ml, and T 1/2 was 2.77 +/- 0.32 hours on the average. 3. Serum concentrations of AZT in 2 neonates given AZT 25 mg/kg reached their peaks at the end of intravenous drip infusion at 31.1 and 33.4 micrograms/ml with little difference from the 20 mg/kg group. Half-lives of serum AZT in the 2 cases were 1.87 hours and 3.23 hours, respectively. 4. Urinary excretion rates of AZT in 7 neonates younger than 11 days of age in the first 6 to 8 hours after the administration were 18.8 to 50.0%, or 31.7% on the average, which was lower than the average excretion rate found with infants. 5. All the cases given AZT showed clinical results rated better than "effective". Effect of AZT was excellent on 3 UTI cases caused by Escherichia coli and Klebsiella pneumoniae, but bacterial replacement (superinfection) of Enterococcus faecalis was observed when AZT was administered. 6. Transient elevations of GOT and GPT were seen in 2 cases when AZT administration was continued at length. Clinical side effect was not observed. 7. The most appropriate dosage and administration scheme of AZT against Gram-negative infections in neonates seems to be 40-60 mg/kg/day, b.i.d. or t.i.d.

Aztreonam↗