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H Albin

Publications and source records attributed to H Albin.

At least 19 recordsLinked to original sources
PubMed1989

The influence of the route of administration of imipramine on imipramine and desipramine blood levels.

Imipramine was used to treat 18 depressed inpatients for 22 days. Imipramine 2 mg/kg/day was administered from day 0 to day 14 intramuscularly, and 4 mg/kg/day was administered orally from days 15-21. Two pharmacokinetic studies were performed, the first at the end of the intramuscular phase (day 14) and the second at the end of the oral phase (day 21). Imipramine and desipramine blood levels were measured every hour from 8 a.m. to 4 p.m. Between these two pharmacokinetic evaluations, blood levels of imipramine and desipramine were measured every morning at 8 a.m. During intramuscular administration, the parent drug imipramine predominated in the plasma and, conversely, the desmethylated metabolite predominated during oral administration. With the changeover in route of administration, the doubling of the dose kept the blood levels of imipramine equal, while desipramine increased; the sum of imipramine and desipramine also increased, and the ratio of imipramine and desipramine decreased sharply, the median ratio changing over 3 days from 1.50 (day 15) to 0.62 (day 18).

Administration, Oral↗
PubMed1988

Pharmacokinetics of rilmenidine in healthy subjects.

Rilmenidine is a novel alpha 2-adrenoceptor agonist, used in the treatment of mild or moderate hypertension at the oral dose of 1 mg once or twice daily. The pharmacokinetic parameters were investigated after single or repeated administration in healthy subjects, using labeled and unlabeled compounds. Rilmenidine was rapidly and extensively absorbed, with an absolute bioavailability factor close to 1 and a maximal plasma concentration achieved within 2 hours. Rilmenidine was not subject to presystemic metabolism. Distribution was independent of the free fraction because rilmenidine was weakly bound to plasma proteins (less than 10%). The volume of distribution was approximately 5 l.kg-1 (315 liters). Elimination was rapid with a total body plasma clearance of approximately 450 ml.min-1 and an elimination half-life of approximately 8 hours. Renal excretion was the major elimination process (two-thirds of the total clearance). Metabolism was very poor, with a renal elimination of rilmenidine as the parent drug (urinary fraction of rilmenidine was about 65% and no metabolite plasma levels were detected). Linear pharmacokinetics were demonstrated for rilmenidine from 0.5 to 2 mg but, at 3 mg, a slight deviation from linearity was observed. In repeated administration, the linear disposition of rilmenidine with dose was confirmed.

Absorption↗
PubMed1988

Pharmacokinetic and metabolic parameters of tianeptine in healthy volunteers and in populations with risk factors.

Following oral administration in the fasting healthy subject, the mean maximum concentration of tianeptine is 334 +/- 79 ng/ml. Absorption of tianeptine from the tablet form is rapid and complete. Maximum plasma concentration is obtained by the first hour following administration (0.94 +/- 0.47 h). Absolute bioavailability is 99 +/- 29%. Tianeptine is thus rapidly and completely absorbed in the tablet form and is not subject to first-pass effect. Distribution of tianeptine in the body is characterized by the following: its rapidity, the mean distribution half-life being about 0.7 h; its limited extent, the apparent volume of distribution being about 0.8 L/kg (0.77 +/- 0.31 L/kg); and protein binding, which averages 93.8 +/- 2.4%. Elimination of tianeptine is characterized by a short mean half-life of 2 h 30 min (2.5 +/- 1.1 h) and by renal excretion of 0.4 ml/min (0.4 +/- 0.4 ml/min). Tianeptine is extensively metabolized. Major metabolites are analogs of tianeptine with a C5 and C3 lateral chain and a N-demethylated derivative. Studies have shown negligible influence on pharmacokinetic parameters of chronic alcoholism even in case of hepatic cirrhosis. In renal failure, and in the elderly, studies have revealed a 1-h prolongation of elimination half-life which suggests that the dosage should be limited to two tablets per day in such cases.

Administration, Oral↗
PubMed1988

[Influence of fever on cefotaxime pharmacokinetics].

The role of fever on cefotaxime disposition was studied in ten hyperthermic patients. Each subject received intravenously 1 g of cefotaxime on two separated occasions, first when the body temperature was more than 39 degrees C then during a basal state (37 degrees C). Blood samples were taken over 12 hours and urine was collected for 24 hours after injection. After dosing cefotaxime and its metabolite by high performance liquid chromatography, the pharmacokinetic parameters were calculated, especially: plasma and renal clearance, volume of distribution at steady state, area under the curve, and elimination half-life. There is no significant difference in cefotaxime and desacetylcefotaxime disposition between these two states. Hyperthermia has no influence on pharmacokinetics of this cephalosporin.

Adult↗
PubMed1988

Pharmacokinetics of intravenous and intraperitoneal fosfomycin in continuous ambulatory peritoneal dialysis.

Kinetics of fosfomycin were investigated in six patients undergoing continuous ambulatory peritoneal dialysis. Each subject received both an i.v. and an i.p. 1 g dose of fosfomycin with a one week washout between doses. Fosfomycin was assayed by a microbiological diffusion technique. After intravenous injection the fosfomycin serum kinetic parameters were as followed: elimination half-life (t1/2 beta) 38.4 +/- 8.7 h; volume of distribution 0.32 +/- 0.02 l/kg; total plasma clearance 7.0 +/- 1.4 ml/min and peritoneal clearance 3.2 +/- 0.2 ml/min. Dialyzate fosfomycin concentrations reached a maximum mean value of 32.2 +/- 2.8 micrograms/ml at 4 h post-injection and fosfomycin was detectable in dialyzate samples for up to 72 hours post-dosing. After intraperitoneal instillation, fosfomycin appeared in the serum rapidly and the mean peak plasma concentration was 36.2 +/- 2.8 micrograms/ml at the 4th h. The absorption rate (ka) was 0.580 +/- 0.039 h-1 and the absorption of fosfomycin from peritoneal space was 68.4 +/- 6.0%. These data suggest a bidirectional exchange through the peritoneal membrane. Intraperitoneal administration of 1 g either 48 h apart for anephric patients or 36 h apart for patients with residual renal function may achieve therapeutic serum concentrations.

Female↗
PubMed1987

Pharmacokinetics of ciprofloxacin tablets in renal failure; influence of haemodialysis.

The pharmacokinetics of ciprofloxacin has been studied after a single oral dose of 500 mg given to 5 normal subjects (N) and to 15 patients grouped according to their residual renal creatinine clearance: Group I, 8-30 ml X min-1, Group II, less than 8 ml X min-1, and Group III, haemodialysed patients studied twice--during an interdialysis period (IIIa) and in a 4 h haemodialysis session (IIIb). Ciprofloxacin was assayed by reverse phase HPLC using a spectrofluorimetric detection. The peak plasma concentration (2-5 mg X l-1) was reached within 2 h after drug administration. Apparent volume of distribution, 6.6 (N), 5.0 (I), 2.7 (II) and 4.2 (IIIa) l X kg-1 and total plasma clearance, 770 (N), 440 (I), 378 (II) and 314 (IIIa) ml X min-1 were decreased in relation to the degree of renal impairment. Mean plasma half-lives for patients in the 4 groups were 7.3 (N), 10.4 (I), 7.2 (II) and 9.3 (IIIa) h. In groups N, I and II, 40, 16 and 8% of the administered dose was eliminated through the kidney, with mean renal clearances of 305 +/- 63, 61 +/- 21 and 21 +/- 3 ml X min-1. A linear relationship was found between the renal clearance of ciprofloxacin and the glomerular filtration rate (r = 0.75, n = 15). Ciprofloxacin was partly removed by haemodialysis (IIIb): the dialyser extraction ratio was 23% and the dialysis clearance was 40 ml X min-1.

Administration, Oral↗
PubMed1987

Effects of josamycin on carbamazepine kinetics.

The steady state pharmacokinetics of oral carbamazepine in epileptic patients (n = 8) was compared before and after one week of treatment with josamycin (2 g/day). There was a small but statistically significant decrease in oral clearance of total (17%) and unbound (21.5%) drug. In spite of an unchanged AUC of 10,11-epoxide carbamazepine the ratio of metabolite to parent drug AUC was significantly decreased (20.2%). The plasma protein binding of carbamazepine and its 10,11-epoxide metabolite did not vary. The results demonstrate impairment by josamycin of the apparent clearance of carbamazepine. Care should be taken in patient receiving both carbamazepine and josamycin.

Adult↗
PubMed1987

Effect of aluminum phosphate on the bioavailability of ranitidine.

The effect of aluminum phosphate on the bioavailability of ranitidine has been investigated in 10 young, healthy volunteers. Following a random cross over design, each subject took at a 1 week interval 150 mg ranitidine alone or with 11 g aluminum phosphate. Plasma and urine ranitidine levels were measured by HPLC. The antacid reduced both the maximum plasma ranitidine concentration by 40% and the area under the curve by 30%. Elimination of ranitidine was not changed. The results indicate that aluminum phosphate significantly diminished the bioavailability of ranitidine.

Adult↗
PubMed1987

[Pharmacokinetics of pethidine after spinal anesthesia. Clinical implications].

Eleven male patients undergoing endoscopic resection for prostatic adenoma and bladder tumours under spinal anaesthesia received intrathecal pethidine 1 mg X kg-1. Plasma concentration and its evolution with time were assessed; pethidine plasma concentrations were determined by high performance liquid chromatography. Pethidine was rapidly and extensively absorbed. The peak plasma concentration of pethidine was 176 +/- 66 ng X ml-1 (range: 84-208) and the time to peak concentration was 2.3 +/- 1.4 h (range: 0.5-6 h). The terminal elimination half-life was 7.2 +/- 2.2 h (range: 4-11.5 h). The plasma concentrations of pethidine remained below 500-700 ng X ml-1, the minimum concentration necessary to obtain a systemic analgesic effect. Two patients required noramidopyrine as a complement at the 8th and 12th h respectively. No respiratory depression was observed. Intrathecal pethidine (1 mg X kg-1) was an effective agent for spinal anaesthesia: the prolonged postoperative analgesia was due to the drug acting on opioid receptors in the spinal cord. This led to the necessity of postoperative monitoring during 24 h after intrathecal pethidine administration.

Aged↗
PubMed1987

Pharmacokinetics of roxithromycin in paediatrics.

Macrolides are well known for their high lipid solubility and good tissue penetration. The pharmacokinetic properties of roxithromycin, a new semisynthetic macrolide, appear to be very interesting in healthy adult patients. Five paediatric pharmacokinetic studies are summarized and show that the pharmacokinetic properties of roxithromycin in paediatrics are very similar to those previously reported in adults and suggest that the same dose every 12 h is appropriate in paediatrics, 2.5 mg/kg. The diffusion of roxithromycin into upper respiratory tract tissues appears to be good in children.

Child, Preschool↗
PubMed1987

[In vitro study of the transplacental passage of chloroquine sulfate].

The authors, by performing in vitro perfusion on six human placentas, have studied the passage of chloroquine sulphate into the placenta. The drug levels were recorded by high performance liquid chromatography (HPLC). The placental perfusions lasted one hour and drug passage into placental tissue was low (14.21%) which seems to be due to the high degree of fixation of chloroquine on placental tissue.

Chloroquine↗
PubMed1986

Pharmacokinetics of intravenous and intraperitoneal moxalactam in chronic ambulatory peritoneal dialysis.

The kinetics of moxalactam has been investigated in 10 subjects undergoing continuous ambulatory peritoneal dialysis (CAPD). A single 1 g dose was injected i.v. and a 1 g dose was given intraperitoneally in the CAPD fluid during a 4 h dwell-time. Moxalactam was assayed by HPLC. After i.v. injection, the serum kinetics of moxalactam were: plasma t 1/2 = 17.9 h; volume of distribution at steady-state, 0.27 l/kg; total plasma clearance, 12.8 ml/min; peritoneal clearance, 2.1 ml/min. Dialysate moxalactam concentrations rose rapidly but only 20% of the dose was eliminated by the peritoneal route. After intraperitoneal instillation, moxalactam appeared in the serum rapidly and the peak serum concentration ranged from 21 to 49 micrograms/ml after between 4 and 5 h. The absorption of moxalactam from the peritoneal space was 57 +/- 16%. The data suggest that moxalactam has bidirectional exchange characteristics through the peritoneal membrane. Instillation of moxalactam in CAPD fluid may permit rapid absorption and the appearance of a therapeutic serum concentration.

Adult↗
PubMed1986

Effect of sucralfate on the bioavailability of cimetidine.

Twelve, healthy fasting, subjects received 200 mg cimetidine orally either with water or 1 g sucralfate in a randomized, single dose, two-way crossover study. Blood samples were taken for 12 h and urine was collected for 24 h. Cimetidine in plasma and urine was analysed by HPLC. There was no significant difference between the two treatments in peak plasma concentration, time to peak plasma concentration, area under the plasma concentration-time curve and urinary excretion. The results indicate that sucralfate did not reduce the bioavailability of cimetidine.

Adult↗