Effects of mouth washing procedures on removal of budesonide inhaled by using Turbuhaler.

Mouth washing after inhalation of corticosteroids is effective for prevention of local adverse effects. We determined the amounts of drug residues remaining on the oropharyngeal mucosa following inhalation of budesonide (BUD) via a Turbuhaler (BUD-TH) (100 microg). Further, we studied the effects of mouth washing on the removal of drug residues by quantification of BUD in expectorated wash solution using an HPLC method. The amount of BUD recovered after gargling and rinsing for 5 s each was 19.4+/-9.4 microg, as compared to 23.8+/-13.6 microg after rinsing alone for 10 s and 18.3+/-8.9 microg after gargling alone for 10 s, though the differences were not significant. Our results indicated that about 20% of the dose was remaining on the oropharyngeal mucosa after inhalation. In a comparison of washing times, the amounts of BUD recovered were 26.3+/-3.2 microg after gargling and rinsing for 3 s each, and 19.4+/-9.3 microg after those for 5 s each. As for the effect of lag time before beginning mouth washing, the ratio of BUD recovered following mouth washing with a lag time of 1 min was 73.2%, while it was reduced to 27.8% after 10 min, as compared to immediate mouth washing following administration. Our results suggest that the amount of BUD removed by mouth washing is associated with the lag time between inhalation and mouth washing, however, not with the duration of mouth washing. We concluded that immediate mouth washing after inhalation is most useful for the removal of drugs following BUD-TH administration.

[Analysis of antiemetic effect of various dosage regimens of azasetron hydrochloride based on 5-HT3 receptor occupancy of serotonin].

Antineoplastic drugs have been shown to exert direct effects on the gut and induce the release of serotonin from the enterochromaffin cells of small intestinal mucosa. It is thought that released serotonin stimulates vagal afferent fibers through 5-HT3 receptors located in the vagal afferent terminals in the gastrointestinal tract and initiates sensory signals to the area postrema and the emetic center, thereby initiating nausea and vomiting. A 5-HT3 antagonist competitively inhibits serotonin at its specific binding sites, 5-HT3 receptors, and thereby elicits an antiemetic effect. Therefore 5-HT3 receptor occupancy of serotonin may be an appropriate indicator of the antiemetic activity of 5-HT3 antagonists. We analyzed 5-HT3 receptor occupancy of serotonin by integrating pharmacokinetic and receptor-binding kinetic parameters based on the receptor occupancy theory to compare the strength of the antiemetic effects of three dosage regimens of azasetron hydrochloride. The inhibitory effects on the binding of serotonin to 5-HT3 receptor of regimen 2 (an intravenous bolus injection of 5 mg of azasetron hydrochloride before and 8 h after chemotherapy) and regimen 3 (an intravenous bolus injection of 2.5 mg followed by 7.5 mg continuous intravenous infusion for 24 h) were longer-lasting than those of regimen 1 (an intravenous bolus injection of 10 mg before the start of chemotherapy). Furthermore, a positive relationship was found between the time of inhibitory effects on the binding of serotonin to 5-HT3 receptor and antiemetic effects of azasetron hydrochloride. From these results, dosage regimens 2 and 3 were considered to be more effective in the long term than regimen 1 in prophylaxis of nausea and vomiting induced by cisplatin.

Influence of glutathione S-transferase A1 polymorphism on the pharmacokinetics of busulfan.

BACKGROUND: High-dose oral busulfan is used for myeloablative chemotherapy before hematopoietic stem-cell transplantation. Fatal adverse effects or relapse may occur with excess or insufficient busulfan exposure. Glutathione S-transferase (GST) A1, whose genetic polymorphism in its promoter region has been reported, is responsible for busulfan metabolism. We investigated the polymorphism of GSTA1 on busulfan pharmacokinetics. METHODS: Blood samples (6 or 7 points) were taken from patients receiving high-dose oral busulfan (approximately 1 mg/kg every 6 h) on Doses 1 and 5. Pharmacokinetic parameters were calculated from plasma busulfan concentration. RESULTS: Twelve patients were enrolled in this study. Nine patients were genotyped as wildtype (GSTA1*A/*A), and 3 as heterozygous variants (GSTA1*A/*B). At Dose 5, the heterozygous group had significantly lower elimination constant (0.176+/-0.038 vs. 0.315+/-0.021 h-1; P=0.008) and clearance corrected by bioavailability (0.118+/-0.013 vs. 0.196+/-0.011 l/h/kg; P=0.004), and significantly higher mean plasma busulfan concentration (1344+/-158 vs. 854+/-44 ng/ml; P=0.001) than the wildtype. CONCLUSIONS: This is the first report on the significant influence of GSTA1 polymorphism on busulfan elimination. This may account for the large inter-individual variance in busulfan pharmacokinetics, and with more information confirming our study, busulfan high-dose therapy may be optimized by GSTA1 genotyping in advance.

[Analysis of the factors associated with drugs remaining in the Diskhaler following inhalation of fluticasone propionate].

Because it is well known that drug remains in the fluticasone propionate Diskhaler (FP-DH) following a single inhalation, the following patient information is recommended. "Please inhale more than once or twice if any drug remains in the device after inhalation". It is believed the inspiratory flow rate of the individual patient has an influence on the amount of drug that remains in the device. If the dosing performance of FP-DH is dependent on inspiratory effort, establishment of a method of inhalation that makes it independent of inspiratory flow rate is important in clinical practice. In the present study, we investigated the influence of various methods of inhalation of drug remaining in the FP-DH. No significant differences were observed regarding the drug remaining in the device among the inhalation times examined (range, 0.5-2.5 s) or the number of inhalations (range, 1-3 times). On the other hand, the amount of drug remaining in the device did decrease by tapping the device before the second inhalation. The results suggest that the amount of drug remaining in the device can be decreased by tapping the device after the first inhalation if the patient's inspiratory flow rate is low.

Effects of the CYP3A5 genetic polymorphism on the pharmacokinetics of diltiazem.

BACKGROUND: The cytochrome P450 (CYP) 3A subfamily plays an important role in the metabolism of various endogenous and exogenous compounds. Among CYP3A subfamily members, CYP3A5 is polymorphically expressed and the CYP3A5*3 and CYP3A5*6 alleles are known not to express functional CYP3A5. Thus, these mutant alleles are thought to be responsible for interindividual variability of CYP3A activity. METHODS: Subjects possessing CYP3A5*1/*1, *1/*3 or *3/*3 received oral administration of diltiazem hydrochloride (60 mg), and plasma and urinary concentrations of diltiazem and its metabolite N-desmethyldiltiazem were measured. Before drug intake, cortisol metabolic clearance in each subject was measured to estimate in vivo CYP3A4 activity. RESULTS: The mean values of total oral diltiazem clearance of subjects with *1/*1, *1/*3 and *3/*3 were 183.4 +/- 39.4, 197.9 +/- 49.6 and 293.6 +/- 141.1 (l/h), respectively, and were not significantly different among the 3 genotype groups. The cortisol metabolic clearance was not significantly different among the three genotype groups, indicating that the CYP3A4 activity is not significantly different. CONCLUSION: The results suggest that CYP3A5*3 has only a minor effect on the pharmacokinetics and metabolism of diltiazem. Although our results did not indicate significance of CYP3A5, the effects of CYP3A5*3 on the metabolism of other CYP3A substrates remain to be investigated.

Investigation of mouth washing by patients after inhaling corticosteroids.

We report an effective method for mouth washing after inhalation of corticosteroids for the prevention of local adverse effects such as hoarseness and oropharyngeal candidiasis. This method involves gargling and rinsing immediately after inhalation, repeated at least twice. We performed a questionnaire survey on mouth washing after inhalation of corticosteroids of 19 inpatients who used inhaled corticosteroids at the University of Tokyo Hospital. The questions concerned: 1) awareness of local adverse effects of inhaled corticosteroids; 2) gargling and rinsing habits; 3) repeating mouth washing at least twice; and 4) mouth washing immediately after inhalation. The percentage of patients correctly performing the individual maneuvers were: 1) 63.2%; 2) 36.8%; 3) 36.8%; and 4) 63.2%. The percentage of patients performing our recommended method of mouth washing (all four elements) was 11%. These results suggest that patients receiving inhaled corticosteroids poorly comprehend mouth washing procedures after inhalation of corticosteroids. It is important that pharmacists advise patients on the correct method of mouth washing.

Effects of CYP2D6 genotypes on plasma concentrations of risperidone and enantiomers of 9-hydroxyrisperidone in Japanese patients with schizophrenia.

It has been shown that risperidone (+)-9-hydroxylation is enantioselectively catalyzed by the polymorphic CYP2D6 in human liver. This study aimed to examine the effect of CYP2D6 genotype on (+)-9-hydroxylation of risperidone in schizophrenic patients. Subjects were 38 Japanese schizophrenic inpatients receiving 6 mg/day of risperidone. Plasma concentrations of risperidone and (+)- and (-)-9-hydroxyrisperidone at steady state were quantified using LC/MS/MS and HPLC with alpha 1 acid-AGP chiral column, respectively. The CYP2D6*5(*5) and *10 alleles were identified using polymerase chain reaction (PCR) methods. Twenty patients had no mutated allele, 14 had one mutated allele, and 4 had two mutated alleles. There were significant differences in the steady-state plasma concentrations of risperidone (ANOVA; p < 0.0001) among the three genotype groups, while the CYP2D6 genotype did not affect the steady-state plasma concentrations of (+)-9-hydroxyrisperidone (p = 0.314) or (-)-9-hydroxyrisperidone (p = 0.957). The concentration ratio of risperidone to 9-hydroxyrisperidone was strongly dependent on the CYP2D6 genotypes. This study suggests that CYP2D6 activity strongly influences the steady-state plasma concentrations of risperidone and risperidone/9-hydroxyrisperidone concentration ratios but is unlikely to determine enantio-selectivity in the steady-state plasma concentrations of 9-hydroxyrisperidone in the clinical situation.

Receptor occupancy theory-based analysis of antiemetic effects and standard doses of 5-HT3 receptor antagonists in cancer patients.

PURPOSE: The aim of this study was to determine the usefulness of receptor occupancy theory-based analysis using pharmacokinetic and pharmacodynamic parameters for predicting the average receptor occupancy (PhiB) in humans of each of five 5-HT3 antagonists administered at standard doses. METHODS: The relationship between the PhiB value and the complete vomiting inhibition rate after a single intravenous administration of cisplatin (not less than 50 mg/m2) was analyzed. RESULTS: The predicted PhiB values after intravenous administration and oral administration of 5-HT3 antagonists were more than 65% and 50%, respectively, suggesting that relatively high receptor occupancy is required to elicit sufficient antiemetic effects of 5-HT3 antagonists. Moreover, significant ( P<0.05) linear relationships were found between PhiB values and complete vomiting inhibition rates of 5-HT3 antagonists in preventive cisplatin therapy, with correlation coefficients higher than 0.9, suggesting that the 5-HT3 receptor occupancy is an appropriate index of clinical efficacy of 5-HT3 antagonists, with higher receptor occupancy indicating more extensive antiemetic action. CONCLUSION: The receptor occupancy theory-based analysis of the antiemetic effect of a 5-HT3 receptor antagonist used in this study should be very useful for not only estimating a rational dosage regimen but also determining the standard dose of a new drug using experimental data obtained in a preclinical study.

Metabolic activity of dextromethorphan O-demethylation in healthy Japanese volunteers carrying duplicated CYP2D6 genes: duplicated allele of CYP2D6*10 does not increase CYP2D6 metabolic activity.

BACKGROUND: This study was designed to assess the metabolic activities of dextromethorphan O-demethylation in healthy Japanese subjects carrying duplicated CYP2D6 alleles, CYP2D6*1 x 2, CYP2D6*2 x 2 or CYP2D6*10 x 2. METHODS: Forty-one unrelated healthy Japanese subjects containing carriers who had previously been genotyped as CYP2D6*1 x 2/*2, CYP2D6*1/*2 x 2, and CYP2D6*10/*10 x 2 were phenotyped with dextromethorphan. RESULTS: The metabolic ratios of dextromethorphan/dextrorphan in subjects with CYP2D6*1 x 2/*2 or CYP2D6*1/*2 x 2 were lower than those in subjects with CYP2D6*1/*2, while the metabolic ratios in subjects with CYP2D6*10/*10 x 2, as well as homozygotes for CYP2D6*10, were significantly (P<0.01) higher than those in homozygotes for CYP2D6*1. CONCLUSIONS: The results suggested that carriers with three functional CYP2D6 genes, CYP2D6*1 x 2/*2 or CYP2D6*1/*2 x 2, are ultrarapid metabolizer phenotypes in Japanese. The results also suggested that there is no gene-dose effect with the dextromethorphan O-demethylation activities between carriers with two and three CYP2D6*10 mutated genes per genome. Therefore, CYP2D6*10 x 2 may play an important role for the treatment of Japanese patients as well as CYP2D6*10 which is mainly responsible for the intermediate metabolizers in Japanese.

A long PCR assay to distinguish CYP2D6*5 and a novel CYP2D6 mutant allele associated with an 11-kb EcoRI haplotype.

BACKGROUND: We found a genomic DNA (N=1) associated with an unidentified 11-kb EcoRI haplotype of CYP2D6 and with amplification of the CYP2D6*5 specific polymerase chain reaction (PCR) product without the 11.5-kb XbaI haplotype in a Japanese woman. We developed a long PCR assay to distinguish CYP2D6*5 and the novel mutant allele, and we evaluated the PCR method on 162 different genomic DNA samples. METHODS: Long PCR assays were performed to amplify a fragment specific for the novel mutant allele and to exclude coamplification of CYP2D6*5. RESULTS: A 1692-bp PCR product was amplified from the DNA sample with the novel mutant allele, while the PCR product was not amplified from any of the 162 DNA samples. CONCLUSIONS: The long PCR assay enabled the detection of the novel mutant allele associated with an 11-kb EcoRI haplotype. Further population studies are required to confirm the frequency of the novel mutant allele in various populations, as it may be contained in samples reported as CYP2D6*5.

Thiopurine S-methyltransferase activity in Japanese subjects: metabolic activity of 6-mercaptopurine 6-methylation in different TPMT genotypes.

BACKGROUND: Thiopurine S-methyltransferase (TPMT), which exhibits autosomal codominant polymorphism, plays an important role in the metabolism of thiopurine drugs such as mercaptopurine, thioguanine and azathioprine. Decreased activity of TPMT is associated with severe hematopoietic toxicity after administration of standard doses of these drugs. METHODS: We developed a specific high-performance liquid chromatographic (HPLC) assay for measuring 6-methylmercaptopurine (6-MMP) formed from 6-mercaptopurine (6-MP) in red blood cells (RBC) lysates. The assay was used to study the distribution of TPMT activities in 44 healthy Japanese subjects with different TPMT genotypes. RESULTS: The TPMT activities in the subjects ranged from 17.9 to 37.1 pmol/h/mgHb. The TPMT activity of one subject with TPMT*1/*3C (17.9 pmol/h/mgHb) was 40% lower than the mean value of TPMT activities in 43 subjects with TPMT*1/*1 (29.6+/-4.3 pmol/h/mgHb). CONCLUSIONS: This sensitive and reproducible HPLC assay for determination of TPMT activity in RBC clinical studies has been designed to optimize dosage regimens of thiopurine drugs.

Effects of single and repeated treatment with itraconazole on the pharmacokinetics of midazolam in rats.

To estimate the influence of repeated administration of drug metabolism inhibitors on the extent of drug interaction, we investigated the effects of single intravenous or repeated oral administration of itraconazole on the pharmacokinetics of midazolam in rats. In the single administration study, the plasma concentration of itraconazole was maintained by intravenous infusion, and midazolam was administered into the portal vein to investigate its kinetics. In the repeated administration study, the kinetics of midazolam was investigated after seven-day oral treatment with itraconazole. The in vitro metabolism of midazolam and the contents of cytochrome P450 were investigated using liver microsomes from the itraconazole-treated rats. The area under the curve (AUC) of midazolam was increased by 1.45- or 1.44-fold after single or repeated itraconazole treatment, respectively. Meanwhile, the liver concentrations of itraconazole after single administration and repeated administration were 38.2 and 20.3 (nmol/g), respectively. In vitro maximum metabolic reaction velocity (V(max)) and Michaelis-Menten constant (K(m)) of midazolam were increased from 2.26 to 3.84 (nmol/min/mg protein) and from 8.28 to 13.0 (microM) by single itraconazole treatment, respectively, and decreased from 2.23 to 1.17 (nmol/min/mg protein) and from 7.86 to 4.47 (microM) by repeated treatment, respectively. Correspondingly, the content of CYP3A2 was significantly altered by single or repeated itraconazole administration. The increases in AUC could be predicted only when the changes in V(max) and K(m) were taken into consideration, in addition to the hepatic unbound concentration of itraconazole. In conclusion, changes in enzyme kinetics should be taken into account to predict the extent of drug interaction after repeated treatment with inhibitors.

CYP3A4*18: it is not rare allele in Japanese population.

We sequenced all 13 exons of the CYP3A4 gene derived from 48 Japanese subjects. One subject possess the 20070 T>C mutation in the exon 10 (result in leu293Pro substitution, namely CYP3A4(*)18), as heterozygote. Thus, we investigated the frequency of CYP3A4(*)18 in 118 Japanese population using polymerase chain reaction-restriction fragment length polymorphism with Msp I and determined that the frequency of the CYP3A4(*)18 allele was 1.3%.

Association of troglitazone-induced liver injury with mutation of the cytochrome P450 2C19 gene.

An anti-diabetic agent, troglitazone, was withdrawn from the market because of its association with liver injury. However, the mechanism of the injury has not been elucidated. We examined, retrospectively, the frequency of the polymorphisms of the cytochrome P450 (CYP) 2C19 and 2D6 genes in eight patients with type 2 diabetes who had troglitazone-induced liver injury and 31 subjects who tolerated troglitazone well. Polymorphisms of CYP 2C19 and 2D6 genes were analyzed by polymerase chain reaction using peripheral white blood cells. The incidence of mutations was compared with known population data for the Japanese. Homozygous or compound heterozygous mutations in CYP 2C19 alleles were found in four of the eight (50.0%) patients with troglitazone-induced liver injury. This rate was significantly higher than that in patients without liver injury (four of 31, 12.9%). The frequency of P450 2D6 mutations was the same in both groups. In conclusion, troglitazone-induced liver injury occurred more frequently in subjects with the CYP 2C19 mutations in Japanese patients.

Frequent occurrence of CYP2D6*10 duplication allele in a Japanese population.

Allele-specific long-polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism (RFLP) and haplotype analysis using XbaI and EcoRI were used to determine whether gene duplication of CYP2D6*10 exists in a Japanese population of 162 healthy subjects. Based on the results of PCR and haplotype analysis, the frequencies of CYP2D6*1X2, CYP2D6*2X2 and CYP2D6*10X2 in the Japanese population were estimated to be 0.3, 0.3 and 0.6%, respectively. The results suggest that duplicated alleles of CYP2D6*10 exist in the Japanese population and that it may be one of the factors affecting the capacity of Japanese to metabolize various CYP2D6 substrate drugs.

Inhibitory effect of erythromycin on potassium currents in rat ventricular myocytes in comparison with disopyramide.

Disopyramide, a class Ia antiarrhythmic agent, has been reported to induce torsades de pointes (TdP) associated with excessive QT prolongation in electrocardiogram (ECG), especially when concomitantly administered with erythromycin, a macrolide antibiotic agent. In this study, we have evaluated the effects of erythromycin on action potential duration (APD) and potassium currents in rat ventricular myocytes in comparison with disopyramide. We have evaluated the relationship between in-vitro potassium current inhibition and in-vivo QT prolongation observed in a previous study. Action potentials and membrane potassium currents, including delayed rectifier current (I(K)) and transient outward current (I(to)), were recorded using a whole-cell patch clamp method in enzymatically-dissociated ventricular cells. Erythromycin and disopyramide prolonged APD in a concentration-dependent manner. Disopyramide (10-100 microM) and erythromycin (100 microM) led to increases in the APD at 90% repolarization level. Disopyramide reduced I(K) (IC50 = 37.2 +/- 0.17 microM) and I(to) (IC50 = 20.9 +/- 0.13 microM) while erythromycin reduced I(K) (IC50 = 60.1 +/- 0.29 microM) but not I(to). The observed prolongation of APD might be ascribed to the inhibition of potassium currents. Erythromycin produced the prolongation of APD and the inhibition of potassium currents with a lag time after addition of the drugs, which suggested that erythromycin might not reach potassium channels from outside the ventricular cells. The potency of disopyramide was almost equivalent under in-vitro and in-vivo conditions. However, potency of erythromycin in-vitro was far weaker than that in-vivo reported in a previous study, presumably due to a difference in the uptake of erythromycin into ventricular myocytes between in-vivo and in-vitro conditions. Therefore, when drug-induced risks of QT prolongation are to be evaluated, the difference of potencies between in-vitro and in-vivo should be taken into consideration.

Pharmacokinetic/pharmacodynamic analysis of neutrophil proliferation induced by rhG-CSF in patients receiving antineoplastic drugs.

In the present study, we analyzed the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutrophil counts in cancer patients undergoing chemotherapy using a previously developed pharmacokinetic/pharmacodynamic model.(7)) The time profiles of neutrophil counts in blood after repeated administration of rhG-CSF to lung cancer patients undergoing chemotherapy could be analyzed by this model by considering the inhibition of neutrophil production by antineoplastic drugs. Although deviation was observed between the predicted and observed neutrophil counts in ovarian cancer patients, it may be possible to use this model for determining a rational dosage regimen of rhG-CSF for patients undergoing chemotherapy.

[Evaluation of the permeability of corticosteroid in hairless mouse and hairless micropig skin from admixture of commercially available corticosteroid ointments and/or creams].

Yucatan hairless micropig (YHMP) skin has been shown to have histology and physiologic properties similar to human skin. To assess the relationship between the permeability of corticosteroid ointments and five types of commonly used admixtures of corticosteroid through hairless mice (HM) or YHMP skin and the clinical effects in humans, we conduct by in vitro experiments using HM and YHMP skin. The permeability of corticosteroid in admixtures with urea or heparinoid ointments across HM or YHMP skin was 1.5-4-fold greater than that of corticosteroid ointments alone. HM skin was found to have faster permeability than YHMP skin, but otherwise was similar to YHMP skin. These experiments demonstrated a close relationship between the permeability of HM or YHMP skin and vasoconstrictor activity in humans. These results suggest that the in vitro permeability of corticosteroid measurements across HM skin could be a useful, rapid, and easy method for assessing the vasoconstrictor activity of topical corticosteroids and the admixtures of commercially available ointments and/or creams in humans.

[Creation and usefulness of the "drug information card" for support of dispensing].

We placed a "drug information card" on each medication shelf to assist dispensing by pharmacists, education of students, and risk management of pharmaceutical practices at the Department of Pharmacy, University of Tokyo Hospital. To provide appropriate information items on the drug information cards, we conducted questionnaire survey of 41 pharmacists on the utility of the cards and reviewed questions received from medical staff in the drug information section in our hospital. Based on the results of these investigations, "usage and dosage," "interactions," "contraindications," "product name," and "effects" were printed as basic information items on the drug information cards. Furthermore, information on pharmacokinetics was added. To make maintenance easier, we classified drug information items into "renew often" and "not so often." A good response on the use of the drug information cards was received for dispensing support from 38 pharmacists (92.7%), 14 trainees (100%), and 16 students (94.1%) in the questionnaire investigation. The drug information cards make it possible to obtain precise information rapidly in pharmacies.

Development and evaluation of pharmaceutical services in the ICU/CCU by medical staffs.

Questionnaires were sent out to the staffs (13 physicians, 52 nurses and 5 medical engineers) of the ICU/CCU at the University of Tokyo Hospital, to evaluate pharmaceutical services by analyzing problems in the services offered. Four components of pharmaceutical services were evaluated: inventory control of drugs, check of drug usage and doses, mixing of injections, and offering drug information. Almost all responses from medical staffs evaluated pharmaceutical services overall as "good". The high response rate (96%) from the nursing staff was attributed to the fact that they were familiar with the pharmacist's role with drug inventory, and mixing injections, when nursing was not available for these tasks. Although 50% of physicians rated the pharmaceutical services of providing drug information as "good", this value was lower than responses on other items of the questionnaires, which suggests some dissatisfaction. The occurrences of drug information obtained by passive offering (121 subjects) was 4 times as common as drug information obtained by active offering (30 subjects). From this finding, and comments on the questionnaires from physicians, it suggests that physicians require more drug information for dosage regimens, and prefer the drug information to be provided more actively. Further, an important comment from physicians and nurses was that the services of pharmacists are not available on all shifts/all days of the week to provide consultation for drug information and mixing of injections. Although having a pharmacist available daily around the clock is desirable and ideal to the medical team, the number of pharmacists under the present system cannot support this. As a solution, we think that it is crucial that pharmacists educate medical staff when they are present to in order to optimize therapy and patient care over time.