Search PubMed⌕ Search

Biomedical subjects

L Bertilsson

Publications and source records attributed to L Bertilsson.

At least 235 records · Page 13Linked to original sources
PubMed1975

Plasma kinetics of carbamazepine and its epoxide metabolite in man after single and multiple doses.

Carbamazepine (Tegretol) was administered orally to four patients as a single dose, and one week later three times daily for 15-21 days. The plasma half-lives of the drug were shorter in all patients after multiple doses (20.9 +/- 5.0 hours) than after the initial single dose (35.6 +/- 15.3 hours). During the multiple dose the plasma concentrations of the metabolite carbamazepine-10,11-epoxide followed those of the parent drug. The steady-state plasma concentrations expected during multiple doses were calculated from the pharmacokinetic parameters obtained in the single dose studies. The calculated levels were higher (17.2+/-7.2 mug/ml) than the observed maximal concentrations (8.4+/-1.6 mug/ml on day 4), which were obtained 3-4 days after starting the multiple doses. The levels tended to decrease further during the experimental period. The results suggest that carbamazepine induces its own metabolism in man.

Carbamazepine↗
PubMed1975

Disposition of placentally transferred carbamazepine (Tegretol) in the newborn.

The plasma elimination of carbamazepine (Tegretol) was studied in five newborns who had got the drug transplacentally from their epileptic mothers. The half-lives ranged from 8.2-27.7 hours which is comparable or even shorter than those found in adults after a single oral dose, but in the same range as those found in adults after multiple oral doses. This suggests that the newborns' drug metabolizing capacity has been induced during fetal life.

Carbamazepine↗
PubMed1975

Distribution and elimination kinetics of carbamazepine in man.

Carbamazepine (2.7-3 mg/kg) was administered orally as an alcoholic solution (50% v/v) to eight healthy volunteers. Two of the subjects were also given 50 mg and 100 mg of carbamazepine in alcoholic solution and 200 mg as a tablet. Plasma concentrations, which were analysed by mass fragmentography, reached a maximum 1-7 hours after dosing, and then declined monoexponentially with half-lives ranging from 24 to 46 hours. The half-lives were independent of dose. The apparent distribution volume ranged from 0.79 to 1.40 1/kg. It was found that 72% of carbamazepine was bound to plasma proteins with little interindividual variation, and this was not influenced by the presence of diphenylhydantoin or phenobarbital in therapeutic concentrations. The pharmacokinetic parameters calculated from single oral doses were used to predict the steady-state plasma concentration expected after treatment with multiple doses of 200 mg three times daily. The predicted steady-state concentration was 2-3 times higher than that reported in patients undergoing chronic treatment with carbamazepine at this dose level, i.e. the pharmacokinetics of carbamazepine apparently change during multiple dosing.

Administration, Oral↗
PubMed1975

Determination of carbamazepine and its epoxide metabolite in plasma by high-speed liquid chromatography.

A liquid-chromatographic method for the simultaneous determination of carbamazepine and its active metabolite (carbamazepine 10,11-epoxide) in plasma has been developed. The two compounds were identified in plasma by mass spectrometry. The lower limit of sensitivity is about 4 and 40 ng for the drug and its metabolite, respectively. 10,11-Dihydrocarbamazepine is used as internal standard for the determinations, which have precisions of 2.2 and 4.2%, respectively. No derivatization is needed. The specificity of the method for carbamazepine is shown by the significant correlation (r = 0.99) between the results obtained by this method and by mass fragmentography for the drug in plasma of patients.

Absorption↗
PubMed1975

Pharmacokinetics of indomethacin.

Plasma concentrations of indomethacin have been studied in 5 healthy volunteers after single and multiple doses (25 mg intravenously [iv], 25, 50, and 100 mg orally, 100 mg rectally, and 25 mg three times daily [tid]. In 8 other normal subjects and in 5 patients a 50-mg oral dose of indomethacin was given and the indomethacin concentration was followed from 8 to 32 hr after dosing. All analyses were carried out using a new mass fragmentographic method. After oral and rectal doses the plasma decay of indomethacin was biphasic, and the data were interpreted according to a 2-compartment open model. The half-life of the beta-phase varied between 2.6 and 11.2 hr. The volume of distribution ranged from 0.34 to 1.57 L/kg and the plasma clearance from 0.044 to 0.109 L/kg/hr. There was no evidence of dose-dependent elimination. Indomethacin was rapidly and well absorbed after oral dosing with peak plasma concentrations within 2 hr. Comparison with the area under the curve (AUC) after iv dosing indicated complete bioavailability. The AUC after rectal dosing indicated complete bioavailability, but the rate of absorption was slower than after oral administration. Indomethacin, 25 mg three times daily, was also given for 9 days to the same normal subjects; equilibrium concentrations obtained did not differ significantly (p greater than 0.1) from those predicted from single-dose data in the 5 subjects.

Administration, Oral↗
PubMed1972

Indole-3-acetic acid in human cerebrospinal fluid: identification and quantification by mass fragmentography.

Indole-3-acetic acid has been identified in human cerebrospinal fluid by the gas chromatographic-mass spectrometric technique called mass fragmentography. A specific and sensitive method for quantitative determination of indole-3-acetic acid down to 2 nanograms per milliliter of cerebrospinal fluid has been developed. Samples of cerebrospinal fluid from 24 patients with depression contained 6.1 +/- 3.1 (range 2.6 to 15.8) nanograms of indole-3-acetic acid per milliliter.

Chromatography, Gas↗