Search

Your search keyword '"Chin B"' showing total 7 results
Start Over Author "Chin B" Journal european journal of clinical pharmacology
7 results on '"Chin B"'

6. Replacement of (R)-methadone by a double dose of (R, S)-methadone in addicts: interindividual variability of the (R)/(S) ratios and evidence of adaptive changes in methadone pharmacokinetics

Author

Markus Gastpar, K. Powell, Pierre Baumann, T. Finkbeiner, Chin B. Eap, and Norbert Scherbaum

Subjects
Adult, Male, Methadone maintenance, Substance-Related Disorders, media_common.quotation_subject, medicine.medical_treatment, Pharmacology, Pharmacokinetics, medicine, Humans, Pharmacology (medical), Antidote, Chromatography, High Pressure Liquid, media_common, medicine.diagnostic_test, Double dose, business.industry, Addiction, Stereoisomerism, General Medicine, Analgesics, Opioid, Therapeutic drug monitoring, Anesthesia, Female, Enantiomer, business, Methadone, medicine.drug
Abstract

Methods: Twenty-two patients receiving (R)-methadone maintenance treatment were switched to a double dose of (R, S)-methadone: blood samples were collected before and after the change, and the concentrations of the enantiomers were measured. In the second period, during racemic methadone treatment, important interindividual variability in the stereoselective disposition of the enantiomers of methadone was measured, with (R)/(S) ratios ranging from 0.63 to 2.40. This point should be taken into account particularly with respect to therapeutic drug monitoring of racemic methadone. Results: A significant decrease P < 0.005 in the mean serum concentration/dose ratios of the active (R)-enantiomer before and after the change was measured (mean 3.97 and 3.33). Conclusion: Although of small amplitude (16%), this decrease confirms previously described adaptive changes in methadone pharmacokinetics during racemic methadone maintenance treatment and may necessitate, in some patients, a dose adjustment.

Published
1996
Full Text
View/download PDF

7. Oral administration of a low dose of midazolam (75�?g) as an in vivo probe for CYP3A activity

Author

Gabriela Bleiber, Amalio Telenti, Thierry Buclin, Gianni Cucchia, Kerry Powell Golay, Daniele Fabio Zullino, Reinhold Kerb, Elisabeth Hustert, Pierre Baumann, Anne-Catherine Aubert, and Chin B. Eap

Subjects
Adult, Male, genetic structures, CYP3A, medicine.drug_class, Midazolam, Pharmacology, Hypnotic, Oral administration, In vivo, mental disorders, medicine, Cytochrome P-450 CYP3A, Humans, heterocyclic compounds, Pharmacology (medical), Cross-Over Studies, Dose-Response Relationship, Drug, Chemistry, Oxidoreductases, N-Demethylating, General Medicine, Middle Aged, Aryl Hydrocarbon Hydroxylases, Enzyme Induction, Female, Ketoconazole, surgical procedures, operative, Anesthesia, Sedative, psychological phenomena and processes, Rifampicin, medicine.drug
Abstract

OBJECTIVE: We investigated whether the oral administration of a low dose (75 micro g) of midazolam, a CYP3A probe, can be used to measure the in vivo CYP3A activity. METHODS: Plasma concentrations of midazolam, 1'OH-midazolam and 4'OH-midazolam were measured after the oral administration of 7.5 mg and 75 micro g midazolam in 13 healthy subjects without medication, in four subjects pretreated for 2 days with ketoconazole (200 mg b.i.d.), a CYP3A inhibitor, and in four subjects pretreated for 4 days with rifampicin (450 mg q.d.), a CYP3A inducer. RESULTS: After oral administration of 75 micro g midazolam, the 30-min total (unconjugated + conjugated) 1'OH-midazolam/midazolam ratios measured in the groups without co-medication, with ketoconazole and with rifampicin were (mean+/-SD): 6.23+/-2.61, 0.79+/-0.39 and 56.1+/-12.4, respectively. No side effects were reported by the subjects taking this low dose of midazolam. Good correlations were observed between the 30-min total 1'OH-midazolam/midazolam ratio and midazolam clearance in the group without co-medication (r(2)=0.64, P

Published
2004
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results