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1.
J Chromatogr B Biomed Sci Appl ; 761(1): 85-92, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11585135

RESUMO

A selective gas chromatography-mass spectrometry method using solid-phase extraction has been developed for the detection and quantification of naltrexone and its metabolite, 6,beta-naltrexol in plasma and milk from humans and sheep at pharmacologically relevant concentrations. Di- or tri-acetyl derivatives were formed and quantified by selected-ion monitoring. Recoveries of naltrexone (30 microg/l) and 6,beta-naltrexol (250 microg/l) from both human plasma and milk were greater than 70%. Intra-assay and inter-day precision ranged from 3 to 21% for naltrexone and 2-18% for 6,beta-naltrexol for all matrices investigated, with an overall mean accuracy of 104% for naltrexone, and 99% for 6,beta-naltrexol. Human samples containing these analytes were stable for at least 3 weeks at -20 degrees C or 6 weeks at -80 degrees C. Analysis of the plasma and milk from the lactating sheep showed mean milk-to-plasma ratios of 55 for naltrexone and 3 for 6,beta-naltrexol.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Lactação , Leite/química , Naltrexona/análise , Antagonistas de Entorpecentes/análise , Animais , Humanos , Naltrexona/análogos & derivados , Naltrexona/sangue , Naltrexona/farmacocinética , Antagonistas de Entorpecentes/sangue , Antagonistas de Entorpecentes/farmacocinética , Reprodutibilidade dos Testes , Ovinos
2.
Br J Clin Pharmacol ; 49(3): 223-30, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10718777

RESUMO

AIMS: Gliclazide pharmacokinetics and pharmacodynamics were assessed in 9 Caucasians and 10 Australian Aborigines with uncomplicated type 2 diabetes. METHODS: Subjects were on a stable dose of 80 mg gliclazide twice daily, took 160 mg on the morning of study and had a standard breakfast. No further gliclazide was given over the next 48 h. Regular blood samples were drawn for serum glucose, insulin and gliclazide assay. Gliclazide was measured using h.p.l.c. Noncompartmental analysis was used to describe primary data. A multicompartment model incorporating entero-hepatic recirculation was fitted to group mean serum gliclazide profiles. RESULTS: The Caucasians were older than the Aborigines (mean +/- s.d. age 53.4 +/- 12.2 vs 40.3 +/- 6.9 years, P < 0.05) but had similar diabetes duration, body mass index and glycated haemoglobin. Noncompartmental analysis revealed no between-group differences in gliclazide kinetics. Post-breakfast serum glucose and insulin responses were also similar apart from a longer time to maximum concentration (tmax) for glucose amongst the Aborigines (2.6 +/- 0.4 vs 2.2 +/- 0. 3 h in Caucasians; P = 0.024). Gliclazide tmax exhibited a skewed unimodal distribution and was not associated with gliclazide maximum concentration, or glucose or insulin responses. Most patients had a serum gliclazide profile suggestive of enterohepatic recirculation and/or biphasic absorption. Model-derived estimates of the extent of putative enterohepatic recirculation were 30% and 20% of dose in Caucasians and Aborigines, respectively. CONCLUSIONS: Gliclazide is equally effective in Caucasian and Aboriginal diabetic patients. The pharmacokinetics of oral gliclazide appear more complex than previously thought. Gliclazide pharmacodynamics are unrelated to rate and extent of absorption, consistent with a threshold concentration for hypoglycaemic effect.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Gliclazida/farmacocinética , Hipoglicemiantes/farmacocinética , Havaiano Nativo ou Outro Ilhéu do Pacífico , População Branca , Adulto , Idoso , Austrália , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Feminino , Gliclazida/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologia
3.
Br J Clin Pharmacol ; 45(5): 453-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9643617

RESUMO

AIMS: To characterise milk/plasma (M/P) ratio and infant exposure, for sertraline and N-desmethylsertraline, in breast-feeding women taking sertraline for the treatment of depression. METHODS: Eight women (mean age 28 years) taking sertraline (1.05 mg kg(-1) day(-1)) and their infants (mean age 5.7 months) were studied. Sertraline and N-desmethylsertraline in plasma and milk were measured by high-performance liquid chromatography over a 24 h dose interval at steady-state. M/P values were estimated from area under the plasma and milk concentration-time curves. All milk produced was collected over the dose interval. Infant exposure was estimated as the product of actual or estimated milk production, and average drug concentration in milk, normalized to body weight and expressed as a percentage of the weight-adjusted maternal dose. RESULTS: Mean milk production was 321 ml day(-1) (range 34-974 ml). Mean M/P values of 1.93 and 1.64 were calculated for sertraline and N-desmethylsertraline respectively. Infant exposure estimated from actual milk produced was 0.2% and 0.3% of the weight-adjusted maternal dose for sertraline and N-desmethylsertraline (as sertraline equivalents) respectively. When calculated from estimated milk production (0.15 l kg(-1) day(-1)), infant exposure was significantly greater (P<0.0001) at 0.90% and 1.32% for sertraline and N-desmethylsertraline respectively. Neither sertraline nor its N-desmethyl metabolite could be detected in plasma samples from the four infants tested. No adverse effects were observed in any of the eight infants and all had achieved normal developmental milestones. CONCLUSIONS: Irrespective of the method of calculation of infant exposure, the mean total dose of sertraline and its N-desmethyl metabolite transmitted to infants via breast-feeding is low and unlikely to cause any significant adverse effects.


Assuntos
1-Naftilamina/análogos & derivados , Antidepressivos/farmacocinética , Aleitamento Materno , Leite Humano/química , 1-Naftilamina/análise , 1-Naftilamina/farmacocinética , Administração Oral , Adulto , Antidepressivos/análise , Antidepressivos/sangue , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Lactente , Masculino , Leite Humano/metabolismo , Sertralina , Distribuição Tecidual
4.
Br J Clin Pharmacol ; 45(5): 459-62, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9643618

RESUMO

AIMS: To characterise the transfer of venlafaxine (V) and its O-desmethyl metabolite (ODV) into human milk by measuring milk/plasma (M/P) ratio, and to estimate the likely dose received by a breast-fed infant. METHODS: Milk and plasma samples were collected from three lactating women who were taking venlafaxine for depression, and were at steady-state. In two of the patients, venous blood and milk samples were collected 0, 1, 2, 3, 4, 6, 8 and 12 h post dose, while in the third patient a single pair of blood and milk samples was obtained 0.83 h post dose. A plasma sample was obtained from each of their infants. V and ODV were measured in plasma and milk by high performance liquid chromatography. M/P was calculated and infant dose estimated as drug concentration in milk x a milk intake of 0.15 l kg(-1) day(-1), relative to the weight-adjusted maternal dose. RESULTS: Mean M/P for V was 4.1 (range 2.8-4.8) and 3.1 for ODV (range 2.8-3.8). The mean total infant dose (as V equivalents) was 7.6% (range 4.7-9.2%) of the maternal weight-adjusted dose, with approximately equal amounts of V (3.5%) and ODV (4.1%) in the dose. ODV (median 100 microg I(-1)) was detected in the plasma of all three infants. The infants were healthy and showed no acute adverse effects. CONCLUSIONS: These preliminary data show that the total dose of V and ODV ingested by breast-fed infants can be as high as 9.2% of maternal intake. Moreover there were measurable concentrations of ODV in the infants' plasma. We recommend that exposed infants should be observed closely.


Assuntos
Antidepressivos/farmacocinética , Aleitamento Materno , Cicloexanóis/farmacocinética , Leite Humano/química , Adulto , Antidepressivos/análise , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Cicloexanóis/análise , Succinato de Desvenlafaxina , Feminino , Humanos , Lactente , Recém-Nascido , Leite Humano/metabolismo , Distribuição Tecidual , Cloridrato de Venlafaxina
5.
Ther Drug Monit ; 20(1): 30-4, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9485551

RESUMO

Although the manufacturer of the polyclonal fluorescence polarization immunoassay (FPIA) for tricyclic antidepressants (TCA) only recommends its use in the diagnosis of overdose, the assay is nevertheless widely used in therapeutic drug monitoring. Using plasma samples from 337 patients taking one of eight different tricyclic antidepressants, the authors investigated the performance of the TDx assay procedure for eight different TCAs by comparison to specific high-performance liquid chromatography (HPLC) assay methods. The regression correlation between the TDx assay value and that for active tricyclic measured by HPLC was poor (r2 < 0.9) for amitriptyline, clomipramine, dothiepin, and doxepin. The regression line for amitriptyline also had a significant positive y-axis intercept. Moreover, the TDx method overestimated the concentration of active drug to an extent that varied considerably between different TCAs and within the usual therapeutic range for a single TCA. The authors conclude that the TDx assay is probably satisfactory for routine TDM of desipramine, imipramine, nortriptyline, and trimipramine. However, it significantly overestimates therapeutic concentrations of amitriptyline, clomipramine, dothiepin, and doxepin. The use of TDx and HPLC assay methods by different laboratories for sequential therapeutic drug monitoring of TCAs in the same patient may confuse physicians and confound dose adjustment and patient management. Although their study shows that the TDx assay can give satisfactory therapeutic drug monitoring results for some drugs, the authors conclude that its use should be restricted to the evaluation of overdose as recommended by the manufacturer.


Assuntos
Antidepressivos Tricíclicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento de Medicamentos/normas , Imunoensaio de Fluorescência por Polarização/métodos , Overdose de Drogas , Humanos , Polimedicação
6.
Ther Drug Monit ; 19(1): 29-36, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9029743

RESUMO

Information about the pharmacokinetics of felbamate in children is limited. Even though it is claimed that monitoring of felbamate concentrations is unnecessary, many neurologists have requested therapeutic drug monitoring (TDM) for various reasons. This study used the NONMEM program to describe the pharmacokinetics and the influence of other anticonvulsants on the pharmacokinetics of felbamate. Felbamate, carbamazepine (CBZ), phenytoin (PHY), valproate (VPA), and barbiturate serum levels were obtained by our TDM service as requested by the clinician. The clearance and volume of distribution of felbamate were 41.1 ml/h/kg and 908 ml/kg, respectively. CBZ and PHY increased the clearance 49 and 40% while VPA decreased it 21%. Barbiturate had no significant effect. Clearance also decreased with age.


Assuntos
Anticonvulsivantes/sangue , Propilenoglicóis/sangue , Adolescente , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Carbamazepina/sangue , Carbamazepina/farmacologia , Carbamazepina/uso terapêutico , Criança , Interações Medicamentosas , Monitoramento de Medicamentos/métodos , Felbamato , Humanos , Lactente , Fenobarbital/sangue , Fenobarbital/farmacologia , Fenobarbital/uso terapêutico , Fenilcarbamatos , Fenitoína/sangue , Fenitoína/farmacologia , Fenitoína/uso terapêutico , Propilenoglicóis/farmacologia , Propilenoglicóis/uso terapêutico , Convulsões/sangue , Convulsões/tratamento farmacológico , Ácido Valproico/sangue , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico
7.
Br J Clin Pharmacol ; 44(6): 543-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9431829

RESUMO

AIMS: Methadone is widely used in maintenance programs for opioid-dependent subjects. The aims of the study were to quantify the distribution and excretion of methadone in human milk during the early postnatal period and to investigate exposure of breast fed infants to the drug. METHODS: Blood and milk samples were obtained from 12 breast feeding women who were taking methadone in daily doses ranging from 20-80 mg (0.3-1.14 mg kg-1). Blood was also obtained from eight of their infants. Methadone concentration in these samples was quantified by h.p.l.c. The infants were observed for withdrawal symptoms. RESULTS: The mean (95% CI) milk/plasma ratio was 0.44 (0.24-0.64). Exposure of the infants, calculated assuming an average milk intake of 0.15 l kg-1 day-1 and a bioavailability of 100% was 17.4 (10.8-24) microg kg-1 day-1. The mean infant dose expressed as a percentage of the maternal dose was 2.79 (2.07-3.51)%. Methadone concentrations in seven infants were below the limit of detection for the h.p.l.c. assay procedure, while one infant had a plasma methadone concentration of 6.5 microg l-1. Infant exposure to methadone via human milk was insufficient to prevent the development of a neonatal abstinence syndrome which was seen in seven (64%) infants. No adverse effects attributable to methadone in milk were seen. CONCLUSIONS: We conclude that exposure of breast fed infants to methadone taken by their mothers is minimal and that women in methadone maintenance programs should not be discouraged from breast feeding because of this exposure.


Assuntos
Metadona/farmacocinética , Leite Humano/metabolismo , Entorpecentes/farmacocinética , Transtornos Relacionados ao Uso de Opioides/reabilitação , Adulto , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Recém-Nascido , Masculino , Metadona/sangue , Leite Humano/química , Entorpecentes/sangue , Síndrome de Abstinência Neonatal/psicologia , Distribuição Tecidual
8.
Br J Clin Pharmacol ; 41(3): 217-21, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8866921

RESUMO

1. The excretion of a 6 mg subcutaneous dose of sumatriptan in breast milk was studied in five lactating volunteer subjects with a mean age of 27.6 years and a mean body weight of 75 kg. Drug concentrations in milk and plasma over the ensuing 8 h were measured by high-performance liquid chromatography. 2. The mean milk:plasma ratio estimated from the areas under the milk and plasma concentration-time curves (AUC) was 4.9 (95% CI 4.1-5.7), indicating a significant transfer of sumatriptan into the milk compartment. 3. The mean total recovery of drug in milk was estimated to be only 14.4 micrograms (95% CI 6.1-22.7 micrograms), or 0.24% of the 6 mg administered dose. On a weight-adjusted basis this corresponded to a mean infant exposure of 3.5% of the maternal dose (95% CI 0.3-6.7%). 4. If oral bioavailability in the infant is similar to that in adults (14%), the weight-adjusted infant dose is reduced to 0.49%. Furthermore, allowance for reduced clearance in the infant predicts an infant exposure varying from 4.9% in a very premature neonate to 0.7% in a 30 week old infant. 5. Since sumatriptan is usually administered as a single dose at infrequent intervals, the low level of excretion in breast milk suggests that continued breast feeding following its use will not pose a significant risk to the suckling infant. Even this minor exposure could be largely avoided by expressing and discarding all milk for 8 h after the dose.


Assuntos
Leite Humano/metabolismo , Sumatriptana/farmacocinética , Adulto , Feminino , Humanos , Transtornos de Enxaqueca/tratamento farmacológico , Sumatriptana/uso terapêutico
9.
Clin Pharmacokinet ; 29(3): 154-71, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8521678

RESUMO

Antidepressant drugs are among the most commonly encountered causes of self-poisoning. These drugs include tricyclics, tetracyclics, bicyclics and monocyclics, as well as monoamine oxidase (MAO) inhibitors and selective serotonin reuptake inhibitors (SSRIs). Of these, the tricyclic antidepressants (TCAs) are generally more toxic in overdose, with major toxicity usually manifesting within the first 6 hours after overdose. Various studies indicate that patients at risk of toxicity from TCA overdose may be identified by neurological, cardiovascular and electrocardiography status, together with a quantitative estimate of the plasma drug concentration. While there are various methods available for such chemical estimations, the most satisfactory appears to be fluorescence polarisation immunoassay which gives rapid quantitative results for a variety of TCAs. The selective MAO-A inhibitor antidepressants and the SSRIs are relatively nontoxic when taken alone. However, overdoses of combinations of MAO inhibitors and either SSRIs or TCAs with serotonin reuptake blocking activity may result in a serotonin syndrome with a severe or fatal outcome. Features of this syndrome include hyperpyrexia, disseminated intravascular coagulation, convulsions, coma and muscle rigidity, which may not develop until 6 to 12 hours after overdose. While quantitative chemical identification of these drugs following overdose is helpful in confirming the diagnosis, it is not mandatory. The increasing use of MAO-A inhibitors and SSRIs in the treatment of depression suggests that careful clinical observation is required when combination overdoses are suspected.


Assuntos
Antidepressivos Tricíclicos/toxicidade , Antidepressivos/toxicidade , Overdose de Drogas , Antidepressivos/intoxicação , Overdose de Drogas/diagnóstico , Overdose de Drogas/prevenção & controle , Humanos , Inibidores da Monoaminoxidase/toxicidade , Fatores de Risco , Inibidores Seletivos de Recaptação de Serotonina/toxicidade
10.
Br J Clin Pharmacol ; 39(3): 305-11, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7619673

RESUMO

1. The mechanism of the interaction between ciprofloxacin and theophylline was investigated in nine healthy subjects. 2. Subjects were given a single oral dose of theophylline (3.4 mg kg-1), before and after 60 h of ciprofloxacin therapy at a dose of 500 mg twice daily. 3. Ciprofloxacin reduced the oral clearance of theophylline by 19% (-7.73 +/- 6.42 ml kg-1 h-1 (95% confidence limits -12.66, -2.79)). Some subjects (group A, n = 4) showed little decrease in clearance (mean 4.4%; -1.6 +/- 0.7 ml kg-1 h-1 (-2.6, 0.5)), whereas others (group B, n = 5) showed a marked decrease (mean 30%; -12.7 +/- 3.7 ml kg-1 h-1 (-17.2, -8.1)). 4. Comparing groups A and B, the decrease in oral clearance of theophylline in group B could not be ascribed to differences in the AUC of ciprofloxacin. Group A subjects showed only slight inhibition of 1-demethylation (-12.8 +/- 5.5% (-21.5, -4.0)), while group B subjects showed a significantly greater inhibition of 1-demethylation (-49.9 +/- 9.8% (-62.1, -37.7)), 3-demethylation (-44.8 +/- 8.6% (-55.4, -34.1)) and 8-hydroxylation (-27.0 +/- 3.7% (-31.6, -22.4)). 5. The results suggest that inter-individual variability in the inhibition of theophylline metabolism by ciprofloxacin can be attributed to inter-individual differences in the level of CYP1A2 expression and/or in the degree of inhibition of hepatic CYP1A2 and CYP3A4. 6. The interaction between ciprofloxacin and theophylline can be clinically significant.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ciprofloxacina/farmacologia , Teofilina/farmacocinética , Administração Oral , Adolescente , Adulto , Cromatografia Líquida de Alta Pressão , Ciprofloxacina/administração & dosagem , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/biossíntese , Interações Medicamentosas , Feminino , Polarização de Fluorescência , Humanos , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/biossíntese , Oxirredutases/antagonistas & inibidores , Oxirredutases/biossíntese , Teofilina/administração & dosagem , Teofilina/urina
11.
Xenobiotica ; 24(9): 933-41, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7810174

RESUMO

1. The in vivo disposition of lupanine and 13-hydroxylupanine was studied in subjects identified as poor metabolizers (PM, n = 4) and extensive metabolizers (EM, n = 7) phenotypes for cytochrome P4502D6 (CYP2D6). 2. After oral administration (40.26 mumol), the half-life (t1/2) of lupanine determined from urinary excretion rate studies in EM subjects was 6.2 +/- 0.5 h (mean +/- SEM) with 95.5 +/- 6.0% of the dose recovered unchanged within 72 h. Similarly, in PM subjects t1/2 = 6.5 +/- 0.9 h and recovery 89.9 +/- 4.5%. 3. For orally administered 13-hydroxylupanine (37.83 mumol) the t1/2 in EM subjects was 6.8 +/- 1.0 h with a recovery of 100.5 +/- 5.3%, and in PM subjects t1/2 = 5.9 +/- 1.6 h with a recovery of 102.5 +/- 4.8%. 4. The t1/2s of both lupanine and 13-hydroxylupanine respectively did not differ significantly between EM and PM phenotypes. In addition, total recovery of dose for both alkaloids was similar between phenotypes. 5. In most subjects, > 76% of lupanine and > 85% of 13-hydroxylupanine was recovered as the unchanged compound. Significant apparent partial dehydroxylation of 13-hydroxy-lupanine was observed in one EM (14% of dose) and one PM (34% of dose) subject. 6. Overall, the finding of a high urinary recovery of unchanged lupanine or 13-hydroxylupanine together with similar t1/2s for both alkaloids in EM and PM CYP2D6 phenotypes suggests that clinical toxicity is unlikely to result from the use of lupin seed in footstuffs.


Assuntos
Alcaloides/metabolismo , Alcaloides/farmacologia , Contagem de Células Sanguíneas/efeitos dos fármacos , Análise Química do Sangue , Pressão Sanguínea/efeitos dos fármacos , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Frequência Cardíaca/efeitos dos fármacos , Humanos , Fenótipo , Esparteína/análogos & derivados
12.
Med J Aust ; 159(6): 373-6, 1993 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-8104312

RESUMO

OBJECTIVES: To establish the extent to which participants in the WA methadone treatment program used opiates, cannabinoids, benzodiazepines, cocaine and amphetamines, and to define the pattern of such use over time. In addition, the relationships between methadone daily dose and the use of the various drug groups was examined. DESIGN: A retrospective analysis of data from 1678 samples from urinalysis screening over 13 separate surveys between 1984 and 1991. A mean of 35.9% of patients in the program was sampled on each occasion with each patient contributing only one sample in any one survey. Analytical techniques used included enzyme-multiplied immunoassay, thin-layer chromatography and gas chromatography-mass spectrometry. RESULTS: Methadone and/or its major metabolite were detected in most urine samples, indicating satisfactory compliance by patients. The detection of opiates increased from a mean of 27.1% of samples in 1984-1989 to a mean of 44.2% of samples in 1990-1991. Codeine or morphine were most frequently detected (94% of all opiate-positive samples) and were found together in 38.2% of opiate-positive samples. Detection of cannabinoids also increased from a mean of 45.2% of all samples during 1984-1987 to a mean of 56.4% of samples during 1990-1991. Benzodiazepines were found in a mean of 26.7% of samples but use was not time-related. Detection of amphetamine-class drugs doubled from a mean of 8.3% of all samples (mid 1989 to mid 1990) to 16.8% of samples (mid 1990 to mid 1991). The major representatives of the latter group were methylamphetamine (47.3% of amphetamine-positive urines), amphetamine (15.7%) and ephedrine/pseudoephedrine (44.6%). Opiate use was significantly lower (P < 0.05) in those patients taking more than 80 mg methadone/day. In addition, benzodiazepine use increased significantly (P < 0.05) with increasing methadone daily dose. There was no relationship between methadone daily dose and use of cannabinoids or amphetamines. CONCLUSIONS: The increase in the use of opiates, cannabinoids and amphetamines over the period 1984-1991 occurred about four years after the adoption of a harm minimisation treatment philosophy by the WA methadone program. The high prevalence of codeine and morphine in opiate-positive urine samples strongly suggested the use of "home-bake" heroin. In addition, the data showed that methylamphetamine and ephedrine/pseudoephedrine were the most frequently used psychostimulants. Suppression of opiate use in those clients receiving more than 80 mg methadone/day was consistent with earlier studies. However, the significant increase in use of benzodiazepines with increasing methadone daily dose requires further study.


Assuntos
Metadona , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Transtornos Relacionados ao Uso de Substâncias/urina , Adulto , Anfetaminas/urina , Ansiolíticos/urina , Benzodiazepinas , Canabinoides/urina , Cocaína/urina , Feminino , Humanos , Masculino , Metadona/urina , Entorpecentes/urina , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Austrália Ocidental/epidemiologia
13.
J Clin Periodontol ; 20(8): 606-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8408724

RESUMO

The excretion of lignocaine in breast milk has been documented in a 34-year-old woman following the injection of 20 mg lignocaine for a dental alloy restoration in the right upper quadrant. Lignocaine and its primary metabolite monoethylglycinexylidide in milk and plasma were quantified by high-performance liquid chromatography. The concentration of lignocaine in milk ranged from 44-66 micrograms l-1 while that for monoethylglycinexylidide ranged from 35-41 micrograms l-1. The milk: plasma ratios for lignocaine and monoethylglycinexylidide were 1.1 and 1.8, respectively. The calculated daily infant doses for the parent drug and metabolite were both less than 0.01 mg kg-1 day-1. With the exception of very rare allergic reactions, these levels of infant exposure are extremely low and of no toxicological significance. Nursing mothers receiving lignocaine for standard dental procedures can be advised that continuation of breast feeding is safe.


Assuntos
Anestesia Dentária , Anestesia Local , Lidocaína/análogos & derivados , Lidocaína/farmacocinética , Leite Humano/metabolismo , Adulto , Feminino , Humanos , Lidocaína/administração & dosagem , Lidocaína/análise , Lidocaína/sangue , Leite Humano/química , Fatores de Tempo
14.
Ther Drug Monit ; 14(4): 327-32, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1519308

RESUMO

Monitoring of cyclosporine concentrations in whole blood is used routinely as a guide to adjusting dose so as to achieve optimal therapeutic benefit with minimal adverse effects. In the present study, we have compared a specific high-performance liquid chromatography (HPLC) assay with a fluorescence polarization immunoassay (TDx) and an enzyme-multiplied immunoassay (Emit). Both Emit and TDx assays employ a monoclonal antibody to cyclosporin A and therefore have the potential for a high degree of specificity. Blood specimens (EDTA as anticoagulant) were obtained from 113 patients (71 renal transplants, 17 liver transplants, and 25 other categories) taking cyclosporine and analysed by all three methods. There were significant correlations between results for HPLC and Emit (Emit = 10.54 + 1.07 x HPLC; r2 = 0.82, p less than 0.001) and between results for HPLC and TDx (TDx = 9.16 + 1.42 x HPLC; r2 = 0.82, p less than 0.001). Compared to HPLC analysis, 74% and 96%, respectively, of Emit and TDx results were to the left of the line of identity. The TDx monoclonal antibody appears to have a lesser degree of specificity than that used in the Emit assay. Mean concentrations of cyclosporine measured by Emit and TDx were 17% and 51% higher, respectively, than those measured by HPLC. Because of this overestimation, we suggest that both Emit and TDx methods may find their most appropriate use in routine therapeutic monitoring of renal transplant patients in whom metabolite concentrations are less variable over time.


Assuntos
Ciclosporina/sangue , Anticorpos Monoclonais , Cromatografia Líquida de Alta Pressão/métodos , Estudos de Avaliação como Assunto , Imunoensaio de Fluorescência por Polarização/métodos , Humanos , Técnicas Imunoenzimáticas
15.
Br J Clin Pharmacol ; 33(6): 635-9, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1389937

RESUMO

1. The excretion of dothiepin, nordothiepin, dothiepin-S-oxide and nordothiepin-S-oxide into breast milk was studied in eight women. Exposure to drug was measured in five of their infants, and possible drug-related effects were assessed in all eight infants. 2. Using pre-feed milk samples mean (+/- s.e. mean) milk:plasma (M:P) ratios were 0.78 +/- 0.12, 0.85 +/- 0.16, 1.18 +/- 0.29 and 1.86 +/- 0.29 for dothiepin, nordothiepin, dothiepin-S-oxide and nordothiepin-S-oxide, respectively. In post-feed milk samples, the mean M:P ratio for dothiepin (1.59 +/- 0.32) was significantly greater (P less than 0.05) but M:P ratios for the metabolites were similar. 3. Mean total calculated infant daily doses, (in dothiepin equivalents and as a percent of the maternal dose) were 0.58% for dothiepin, 0.23% for nordothiepin, 2.47% for dothiepin-S-oxide, and 1.17% for nordothiepin-S-oxide. 4. Plasma samples were obtained from five infants. In one, both dothiepin and nordothiepin were below their minimum quantifiable levels (2 micrograms l-1) while in four others both dothiepin-S-oxide and nordothiepin-S-oxide were below their minimum quantifiable levels (10 micrograms l-1). No adverse effects were found in any of the eight infants. 5. Use of dothiepin by depressed mothers is unlikely to be a significant hazard to their breast-feeding infants.


Assuntos
Dotiepina/farmacocinética , Leite Humano/química , Adulto , Cromatografia Líquida de Alta Pressão , Depressão/tratamento farmacológico , Dotiepina/sangue , Dotiepina/metabolismo , Dotiepina/uso terapêutico , Feminino , Humanos , Lactente
17.
Br J Clin Pharmacol ; 32(6): 751-4, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1768569

RESUMO

1. The excretion of indomethacin into breast milk and subsequent exposure of infants was studied in 16 women and seven of their infants. The median milk:plasma ratio in seven patients where there were measurable drug concentrations in both milk and plasma was 0.37. 2. Total infant dose, assuming a daily milk intake of 150 ml kg-1 and 100% absorption, ranged from 0.07% to 0.98% (median = 0.18%) of the weight adjusted maternal dose. 3. Plasma samples were obtained in seven infants. In six of these, indomethacin concentrations were below the sensitivity of the assay (less than 20 micrograms l-1), while one infant had a plasma indomethacin concentration of 47 micrograms l-1. 4. No adverse effects due to indomethacin were reported in the infants.


Assuntos
Indometacina/metabolismo , Leite Humano/metabolismo , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Indometacina/análise , Indometacina/sangue , Recém-Nascido , Masculino
18.
Ther Drug Monit ; 13(6): 485-9, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1771645

RESUMO

Although the tricyclic antidepressant dothiepin is often encountered in deliberate self-poisonings, there are no published studies of its disposition in overdose. In the present study, we have documented the plasma disposition of dothiepin and its major metabolites in eight overdose patients. All had high initial levels of dothiepin (819-3,851 micrograms/L), dothiepin-S-oxide (655-2,162 micrograms/L), nordothiepin (88-422 micrograms/L), and nordothiepin-S-oxide (176-530 micrograms/L) that were considerably above steady-state therapeutic concentrations. In three patients who received treatment with repeated-dose activated charcoal, dothiepin half-lives were 10.6, 12.5, and 13.1 h compared with the literature range of 18.5-24 h. All patients survived and none experienced any significant cardiovascular event despite exhibiting clinical signs of tricyclic antidepressant overdose. We suggest that repeated-dose activated charcoal treatment may decrease the dothiepin half-life after overdose.


Assuntos
Dotiepina/farmacocinética , Intoxicação/metabolismo , Adulto , Carvão Vegetal/farmacologia , Carvão Vegetal/uso terapêutico , Dotiepina/sangue , Dotiepina/intoxicação , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Intoxicação/tratamento farmacológico , Distribuição Tecidual
19.
Rheumatol Int ; 11(4-5): 147-50, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1784882

RESUMO

Intravenous regional administration of corticosteroid (IVRAS) in the treatment of rheumatoid arthritis of the hand has not been reported previously. The method is based on a modification of Bier's block, with substitution of corticosteroid for local anaesthetic. Twenty-two patients were assessed in this double-blind, placebo-controlled study. The technique was safe and effective in improving grip strength, with a group mean improvement of more than 50%. Because suppression of endogenous cortisol production 24 h after treatment was commensurate with the dose of methylprednisolone used (40 mg), we could not exclude that the response may have been due to systemic steroid. Further studies are required to define the real value of IVRAS as it may offer alternative treatment of the joints and tendons within the hand and wrist in some patients rather than more prolonged oral therapy or individual, multiple joint or sheath injections.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Injeções Intravenosas/normas , Metilprednisolona/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Mãos/irrigação sanguínea , Mãos/fisiologia , Humanos , Injeções Intravenosas/métodos , Métodos , Metilprednisolona/administração & dosagem , Fluxo Sanguíneo Regional , Torniquetes , Articulação do Punho/irrigação sanguínea , Articulação do Punho/fisiologia
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