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Solid-phase extraction (SPE) is becoming a commonly used extraction technique. Most existing SPE methods extract a single drug from a relatively clean biological matrix (e.g., plasma, serum, or urine) using a silica-based column. These methods, however, are generally not satisfactory for forensic applications because the majority of biological samples are not as clean (e.g., whole blood, bile, tissues). Silica-based columns also may have reproducibility and stability problems. Polymer-based columns have been developed to overcome some of these limitations. In this study, sequential extraction of acidic, neutral, and basic drugs from whole blood using a polymer-based column, Oasis MCX, was undertaken. The extraction procedure developed involved a conditioning step using methanol followed by water; a three-step wash sequence using water, 0.1 M hydrochloric acid, then water/methanol (95:5); and two elution steps. One elution step was for acidic and neutral drugs utilizing acetone/chloroform (1:1), and a second used ethyl acetate/ammonium hydroxide (98:2) for basic drugs. Of the drugs tested, 75% were extractable from whole blood and detectable at therapeutic concentrations. Good recoveries and clean extracts were achieved for the basic drugs; however, the extracts were not as clean for acidic drugs. Unfortunately, the Oasis MCX procedure was not suitable for extracting all drugs (e.g., benzodiazepines).

Drug expenditures are rising more rapidly than other health care spending. There are a number of reasons for this difference, including the volume of medications available. Optimal drug therapy is the goal for every patient. Physicians and nurses are experiencing difficulty coping with increased health care needs and have not been able to control drug expenditures. Pharmacists, who are trained to deliver pharmaceutical care, should be an integral part of the system. Improved partnerships among patients, physicians and pharmacists have shown conclusively that the pharmacist has an important role in the delivery of health care cost effectiveness. Together, using their respective knowledge base, pharmacists and physicians could provide optimal drug therapy, which would be of benefit to patients and the health care system. This might involve a change in the reimbursement system for pharmacists.

Over 8,000 students in Grades 6 through 12, from Western Canada and the North West Territories were surveyed for the prevalence of licit and illicit drug use over a 1-year period ending June 30, 1992. The results were compared with three previous studies dating back to just over 5 years. While there was a slight decline between 1987 and 1990, the present study reveals a slight reverse in this trend. These results emphasize the need for continued education and perhaps the need for determining the reasons for use by this age group.

Apnea of prematurity is a common problem in neonatal intensive care nurseries. Xanthines are used to treat apnea, but their mechanism of action is not clearly understood. To determine whether xanthines stimulated beta-endorphin (beta-ED) release in preterm infants, plasma beta-ED concentrations were measured in 27 infants with apnea of prematurity. These infants had a mean (+/- SD) birthweight of 1560 +/- 487 g, gestational age 31 +/- 2.5 weeks, and a postnatal age of 7.3 +/- 4.6 d. Twenty-five of the infants were treated with I.V. aminophylline 2.5 mg/kg/dose 4 times daily and 2 were treated orally with caffeine (10 mg/kg). Blood samples were collected prior to and 30 min after treatment with xanthines. Apneic spells greater than 15 sec were recorded and reviewed every 24 h using a Hewlett-Packard Merlin Monitor (Waltham, MA.) system. Infants were then stratified into responders (Group 1, n = 14) and nonresponders (Group 2, n = 13), with responders defined as showing more than 50% decrease in the frequency of apneic spells in the first 24 h of treatment. beta-ED were measured as previously described using a radioimmunoassay technique. In group 1, plasma beta-ED concentration increased significantly, (p = 0.0496) from pre-xanthine (24.4 +/- 12 pg/ml) to post xanthine (34.6 +/- 24 pg/ml) treatment, whereas in Group 2 the concentrations remained the same (23.3 +/- 5 pg/ml) and (22.6 +/- 4 pg/ml). Birthweight, gestational age, postnatal age, and diagnoses in both groups were compared and no significant differences were observed. Interestingly, xanthine treatment caused increased plasma beta-ED release when apneas decreased.

Although the metabolism and pharmacokinetics of chloral hydrate (CH) have been reported, there have been no attempts to correlate CH or its metabolite, trichloroethanol (TCE) with the sedative or hypnotic effects. In order to determine whether plasma concentrations of CH or TCE reflect the sedative/hypnotic effects, a sedation/agitation scale was developed. Based on the results of the present study, the sedative/hypnotic effects of TCE cannot be ruled out completely. However, in the neonate, the parent drug CH seems to have a more important role than has been previously suggested from human research.

Serum sulfate concentrations were determined in volunteers consuming municipal drinking water with varying sulfate contents--77 ppm in Saskatoon and 1157 ppm in Rosetown. The serum sulfate concentrations were subsequently monitored after the administration of single or multiple-dosing regimens of acetaminophen, which undergoes sulfoconjugation, to determine whether sulfate concentrations in serum changed. Average serum sulfate concentrations were 0.35 mmol/L (Saskatoon) and 0.50 mmol/L (Rosetown). Saskatoon volunteers had a significant fall in serum sulfate concentrations during the multiple-dosing regimen. This was not seen in the Rosetown participants. The rates of urinary excretion and renal clearance of sulfate were significantly higher in the Rosetown volunteers. Except for the multiple-dosing t1/2 levels, the Cmax, tmax, AUC and Cl/f of acetaminophen were not significantly different within or between the 2 groups. The excretion of sulfate and glucuronide conjugates of acetaminophen was not significantly different between the 2 groups, but there was a difference within each group with respect to single and multiple-doses. Excretion of the sulfate conjugate fell significantly in the Saskatoon volunteers during the multiple-dose portion of the study, whereas the percentage excreted as the glucuronide increased. The consumption of 15-fold greater sulfate levels in drinking water increased the sulfate concentration in serum. However, this increased concentration did not significantly alter the sulfoconjugation of acetaminophen.

Although the metabolism and pharmacokinetics of chloral hydrate (CH) have been studied in healthy adults, no comprehensive studies have been done in neonates and young infants. Major physiological differences between these groups could greatly affect drug disposition. In this study the patient population (22 patients) was divided into three groups according to postconceptual age: group 1 = preterm infants (31-37 weeks), group 2 = fullterm infants (38-42 weeks) and group 3 = toddler-child patients (57-708 weeks). After receiving one 50 mg/kg oral dose of CH, the parent drug and its metabolites were determined by gas chromatography utilizing an electron capture detector. CH, contrary to what has been reported in the adult, was detectable for several hours after oral administration to patients in all three groups. A highly significant negative correlation was observed amongst the three groups for the half-life (t1/2) and area-under-the-curve for 0 to infinity values for trichloroethanol (TCE), the active metabolite responsible for the sedation effect. The t1/2 value for TCE in group 3 (9.67 h) was similar to that reported for the adult population, but in the less mature subjects it was approximately three (group 2: 27.8 h) to four times (group 1: 39.8 h) greater. Trichloroacetic acid had a remarkably long residence time in the study population after a single dose of CH. The concentration of this metabolite failed to decline even 6 days after dose. These issues should be carefully considered when CH administration is contemplated for clinical use in neonates, infants and children.

A simple, rapid and sensitive electron-capture gas chromatographic method has been developed for the simultaneous determination of chloral hydrate, trichloroethanol and trichloroacetic acid in biological fluids. The described method is applicable to single-dose pharmacokinetic studies of chloral hydrate in the adult. The method also meets the important requirement of using very small sample volumes and is sufficiently sensitive and reliable for disposition studies in the neonate.

In an attempt to determine whether hypoxic-ischemic encephalopathy in and of itself or its associated pathologic conditions lead to increased concentrations of plasma beta-endorphin (beta-ED), measurements were made in three groups of term infants. Group 1 (control) consisted of 8 infants with a mean gestation of 38.6 +/- (SE) 0.4 weeks, a mean birth weight of 3,420 +/- 150 g, and a mean postnatal age of 1.4 +/- 0.7 days. Group 2 consisted of 10 infants with a mean gestational age, birth weight and postnatal age of 40.1 +/- 0.5 weeks, 3,310 +/- 80 g and 3,9 +/- 1.1 days, and group 3 included 6 infants with a mean gestational age, birth weight and postnatal age of 40.4 +/- 1 weeks, 3,650 +/- 310 g, and 2.8 +/- 1 days, respectively. The group 2 and 3 infants suffered clinical and neurological evidence of hypoxic-ischemic brain injury from perinatal asphyxia; however, the infants in group 2 suffered additional problems such as meconium aspiration, persistent fetal circulation with ongoing hypoxemia as measured by transcutaneous or umbilical arterial oxygen monitoring. The group 3 infants were normoxemic after resuscitation. The mean plasma beta-ED concentrations were 19 +/- (SE) 2.7, 103 +/- 35.7 and 25 +/- 4.5 pg/ml in groups 1, 2 and 3, respectively. A significant elevation of plasma beta-ED concentration was observed in group 2 when compared to groups 1 and 3. The association of increased plasma beta-ED concentration in infants with hypoxic-ischemic encephalopathy associated with ongoing hypoxemia suggests that hypoxemia may act as a strong stimulus for plasma beta-ED release in term infants.

Low birth weight preterm infants with suspected infection were administered gentamicin intramuscularly every 18 h (2.5 mg/kg) or 24 h (3.0 mg/kg). For both dosage regimens plasma gentamicin levels were monitored during a dosage interval on three separate occasions over a 10 day period. Both regimens gave satisfactory plasma concentrations and there was no important statistically significant difference between the two. The body clearance of gentamicin correlated with gestational age (r = 0.76, p less than 0.01). The results indicate either regimen may be useful in the clinical situation but from a practical standpoint administration every 24 h may be easier to comply with then every 18 h.

Elaboration of beta-endorphins (beta-ED) is implicated in the modulation of respiratory control in infants. Therefore, beta-ED concentrations were measured in paired samples of CSF and plasma in three groups of infants. Group 1 and group 3 were used as controls. Group 2 infants suffered prolonged apnea of infancy (near-miss sudden infant death syndrome) and were successfully resuscitated. Age and weight (mean +/- SEM) in groups 1, 2 and 3 were 8.5 +/- 3 months and 7.2 +/- 1.4 kg, 3.8 +/- 0.7 months and 5.2 +/- 0.6 kg, and 3.4 +/- 0.9 months and 3.4 +/- 0.7 kg, respectively. CSF beta-ED concentrations were found to be significantly elevated in group 2, 67.8 +/- 4.7 pg/ml, when compared to group 1, 29.8 +/- 3.1 pg/ml, and group 3, 46.5 +/- 7.2 pg/ml (p less than 0.01). No correlation was observed with plasma and CSF concentrations in all three groups. beta-ED may play a role in the pathophysiology of prolonged infant apnea (near-miss sudden infant death syndrome).

A preliminary investigation was undertaken to determine the feasibility of monitoring saliva levels of drugs for forensic purposes. Single oral doses of the title compounds were administered to healthy volunteers. Plasma and saliva levels were measured and ratios calculated for all drugs except diazepam. Saliva/plasma ratios for methaqualone, diphenhydramine and secobarbital were all less than one and reasonably consistent between collection times and subjects. The saliva/plasma ratios for codeine were more variable, but always greater than one. Although more detailed investigation is necessary, saliva may be a useful medium for forensic monitoring of drug ingestion.

Aminoglycoside antibiotics are frequently used for the treatment of suspected and confirmed sepsis in the newborn patient. In an attempt to evaluate gentamicin dosing based on serum creatinine concentrations, two groups of neonates were studied (infants less than 34 weeks n = 8 and greater than 34 weeks n = 14). The dosing interval was adjusted per protocol depending on the serum creatinine concentrations. Analysis of the results indicate reasonable therapeutic serum gentamicin trough and peak concentrations in most infants.

Some 2-benzylidenecyclohexanones, 2,6-bis(benzylidene)cyclohexanones, and related compounds were evaluated for antitumor and cytotoxic activities; (E)-2-benzylidenecyclohexanone (Ia) was shown to have significant cytotoxic properties and a potent inhibitory effect on yeast mitochondria. After intraperitoneal injection of Ia, unchanged drug and a metabolite, tentatively identified as 2-(p-hydroxybenzyl)cyclohexanol, were found in the urine. No metabolites were found in the feces. Oral administration of Ia afforded three unidentified metabolites in the urine and three unidentified metabolites in the feces.

To determine whether a diurnal rhythm exists in neonates admitted to neonatal intensive care units where there is continuous artificial lighting and periodic nursing and medical care, plasma cortisol, adrenocorticotropin (ACTH), and beta-endorphin concentrations were measured in two groups of infants and in adult human volunteers. As expected, a diurnal rhythm was seen in adults. A diurnal rhythm was also found for cortisol and endorphin levels in neonates (3 to 4 days postnatally) with minimal stress and in infants who were clinically severely stressed. There was not a significant difference between the morning and afternoon concentrations of ACTH in these infants, but the afternoon concentrations were lower than the morning's, as would be expected. We found that a diurnal rhythm does exist in neonates within the first few days of postnatal life and that the continuous lighting and medical and nursing interventions do not interfere with this rhythm.

In an attempt to determine whether plasma beta-endorphin (beta-ED) concentrations correlate with occurrence of apnea in preterm infants, measurements were made in three groups of infants. The control group consisted of 11 infants with a mean (+/- SEM) gestational age of 30.5 +/- 0.8 weeks, a mean (+/- SEM) birthweight of 1650 +/- 180 g, and a mean (+/- SEM) postnatal age of 1.3 +/- 0.5 days. Eight infants with apnea, bradycardia, and associated hypotension had a mean (+/- SEM) gestational age, birthweight and postnatal age of 30 +/- 0.9 weeks, 1165 +/- 90 g, and 7.8 +/- 1.9 days, respectively. The third group consisted of eight infants experiencing apnea alone without bradycardia and had a mean (+/- SEM) gestational age, birthweight, and postnatal age of 31 +/- 0.8 weeks, 1380 +/- 125 g, and 2.6 +/- 0.9 days, respectively. The last two groups of infants suffered varying degrees of apnea, but differed in their severity. The plasma endorphin concentrations (+/- SEM) were 26.9 +/- 2, 68.0 +/- 9.0, and 39.6 +/- 2.0 pg/ml, respectively, for the previously described three groups. Significant elevation in beta-ED concentration was observed in the severely apneic infants with bradycardia when compared to the other two groups. The association of increased plasma beta-ED release with severe apneic spells may suggest that these endogenous opiates play a role in the pathophysiology of apnea of prematurity.

This investigation was designed to investigate the effects of ingestion of multiple therapeutic doses of acetaminophen on the disposition of the drug and on the cosubstrate, sulfate. Nine healthy volunteers and nine outpatients receiving acetaminophen for chronic pain were involved in the study. Volunteers were given a single 650 mg oral dose of acetaminophen. One week later they were given 650 mg of acetaminophen every six hours for five doses. Patients were maintained on their normal treatment and dosage schedules (600 mg every 3 to 8 h) for the study. In healthy volunteers the half-life of acetaminophen after single and multiple dosing was not significantly different. However, the fraction of acetaminophen recovered in the urine as the sulfate conjugate was less and the glucuronide conjugate greater after multiple dosing than after a single of the drug. There was no difference in the percentage recovered as the parent compound between single and multiple dosing. Serum sulfate levels fluctuated over the 6-h period following administration of single and multiple doses of acetaminophen to volunteers. The mean serum sulfate concentration was less after administration of five sequential 650 mg doses of acetaminophen than after a single dose. The renal clearance of inorganic sulfate showed a corresponding decrease. Unexpectedly, patients on chronic acetaminophen therapy exhibited elevated serum sulfate levels (levels higher than the maximum sulfate concentration seen in volunteers).

Methods for the simulataneous identification and quantitation of diphenhydramine and methaqualone in urine have been investigated. Suitable thin-layer and gas chromatographic techniques have been developed. The extraction techniques were evaluated by extracting human urine after the ingestion of therapeutic dosages of the two drugs. A charcoal cartridge technique proved to be superior to direct solvent extraction. Although enzyme hydrolysis gave slightly better recoveries than the charcoal cartridge technique, it is a time-consuming procedure.

A catechol metabolite, 5-(3,4-dihydroxyphenyl)-5-phenylhydantoin, and a methylated catechol metabolite, 5-(3-methoxy-4-hydroxyphenyl)-5-phenylhydantoin, were identified as urinary metabolites in humans, monkeys, and dogs following the administration of phenytoin. These metabolites were separated from each other and from other known metabolites of phenytoin as n-butyl derivatives by GLC and positively identified by combined GLC-mass spectrometry.

A high-performance liquid chromatographic (HPLC) assay to quantitate methylparaben in urine was developed. Standard curves were linear and recovery of the paraben from urine averaged 82.6%. The urinary excretion of methylparaben in six preterm infants (less than or equal to 31 weeks gestational age), who were receiving intramuscular injections of a paraben-containing gentamicin formulation, ranged from 13.2 to 88.1%. Small quantities of the metabolite, p-hydroxybenzoic acid, were detected by GC-MS.

A GLC assay to quantitate the methaqualone metabolite 2-methyl-3-(2-hydroxymethylphenyl)-4(3H)-quinazolinone was developed. Standard curves were linear, and recovery of the metabolite from tissue homogenates averaged 89%. In vitro metabolism of methaqualone by the 10,000Xg supernatant fraction of rat liver homogenate was measured by monitoring metabolite formation with the GLC assay. Diphenhydramine inhibited the in vitro metabolism of methaqualone. The percentage inhibition increased with increasing diphenhydramine concentration. The significance of this inhibition in relation to use and abuse of methaqualone--diphenhydramine combinations is discussed.

Plasma beta-endorphin concentrations were measured in two groups of neonates. The control group (group 1) consisted of 20 infants with a mean gestational age of 31.5 +/- 0.6 weeks and a mean birth weight of 1,720 +/- 135 g. Blood samples were collected at a mean postnatal age of 1.0 +/- 0.3 days. Group 2 consisted of 23 infants with clinical evidence of acute illness and associated significant stress who had a mean gestational age of 33.2 +/- 1.1 weeks and a mean birth weight of 2,075 +/- 225 g. Their blood samples were collected at a mean postnatal age of 3.4 +/- 1.3 days. The mean beta-endorphin concentration in group 1 was 27.8 +/- 6 pg/ml and 63.9 +/- 4.2 pg/ml in group 2 (p less than 0.05). No correlation was observed for gestation or birth weight and beta-endorphin concentrations in group 1; however, in group 2 a positive correlation was seen for gestational age and plasma beta-endorphin concentrations (r = 0.4411) suggesting an increased release of plasma beta-endorphin with increasing gestation when faced with significant clinical stress.

Metabolites of doxylamine obtained with rat-liver homogenate in vitro and from urine of Wistar rats and squirrel monkeys in vivo were examined. The metabolites were separated by g.l.c., h.p.l.c. and t.l.c., and tentatively identified through interpretation of their mass-spectrometric behaviour. N-Desmethyldoxylamine was identified in vitro while both N-desmethyl and N,N-didesmethyldoxylamine were detected in rat and monkey urine. The N-acetyl conjugates of N-desmethyl and N,N-didesmethyldoxylamine were tentatively identified both in rat urine and in vitro. Only the N-acetyl conjugate of N,N-didesmethyldoxylamine was detected in monkey urine. In addition, nine other metabolites were tentatively identified in rat urine: N,N-dimethyl-2-[1-(?-hydroxyphenyl)-1-(2-pyridyl)ethoxy]ethanamine; N-methyl-2-[1-(?-hydroxyphenyl)-1-(2-pyridyl)ethoxy]ethanamine; 1-phenyl-1-(2-pyridyl)ethanol; 1-(?-hydroxyphenyl)-1-(2-pyridyl)ethanol; 1-phenyl-1-(2-pyridyl)ethane; 1-(?-hydroxyphenyl)-1-(2-pyridyl)ethane; 2-phenyl-2-(2-pyridyl)ethanol; N,N-dimethyl-2-[1-phenyl-1-(2-pyridyl)-2-hydroxyethoxy]ethanamine; doxylamine pyridine N-oxide. The excretion of doxylamine aliphatic N-oxide in rat urine was confirmed by comparison with the authentic synthetic compound.

Chloral hydrate has been used clinically for over 100 years. There is significant paucity of information regarding chloral hydrate metabolism in neonates and infants. Chloral hydrate and its various metabolites were quantitated in 12 neonates and 2 infants at prescribed time intervals. The analysis of the data indicates accumulation of trichloroacetic acid and trichloroethanol in tissue of compromised infants. There is indirect evidence of competition for hepatic glucuronidation for bilirubin with trichloroethanol in ill preterm infants. Multiple dosing of chloral hydrate in preterm infants should be used with caution and frequent monitoring of serum bilirubin concentrations is indicated in such cases. The mechanism of chloral hydrate metabolism is discussed in detail.

Dimethylamino-1-phenyl-1-penten-3-one hydrochloride (Ia) and 32 analogs were tested for inhibition of respiratory-dependent growth in Saccharomyces cerevisiae. Thirteen of the 33 compounds tested appeared to affect mitochondrial function, since the inhibition of respiratory-dependent growth was statistically greater than the inhibition of growth on fermentable energy sources. Inhibition of mitochondrial function in yeast and growth inhibition of an in vitro culture of human epidermoid carcinoma (KB) were positively correlated since 83% of the compounds tested either had mitochondrial-inhibiting properties and significant activity in the KB test or were inactive in both tests. Similarly, 78% of compounds tested showed murine toxicity and mitochondrial inhibition or had no effect on murine toxicity and yeast mitochondrial function. Injection of Ia into rats resulted in the appearance of blood in the urine and feces. Compound Ia inhibited adenosine diphosphate and collagen-induced aggregation of rat platelets but had no effect on blood clotting. TLC, following incubation of Ia with a rat liver extract, showed that the structure of Ia was not enzymatically modified and indicated activity per se on platelet aggregation and mitochondrial function.

Twelve healthy subjects received three single oral doses (250 mg) of methaqualone alone or in combination with diphenhydramine (25 mg). Blood samples were collected for a 48-hr period after each dose and analyzed for methaqualone and its major metabolite, 2-methyl-3-(2'-hydroxymethylphenyl)-4(3H)-quinazolinone. Peak blood concentrations ranging from 1.0 to 2.7 micrograms/ml occurred approximately 1-2 hr after the oral dose. The area under the blood level-time curve, peak plasma level, and elimination half-life for methaqualone were not significantly different (three-way ANOVA, p greater than 0.05) when methaqualone was administered alone, in combination with a diphenhydramine elixir or as a commercial product (capsule) containing both methaqualone and diphenhydramine. Statistically significant intersubject differences in the area under the curve were eliminated if the area was corrected for subject differences in elimination. Blood levels of the metabolite reached an average peak of 314 ng/ml (+/- 107) between 4 and 8 hr after the dose and remained elevated for the 48-hr sampling period. The areas under the blood level time curve of the metabolite were not significantly different for the three treatments. Diphenhydramine administered at the dosage level used in therapeutic combination products did not alter the blood levels of methaqualone or its metabolite. In addition, no significant differences in methaqualone availability from the two commercial formulations tested could be detected.