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E Andrew

Publications and source records attributed to E Andrew.

61 records · Page 4Linked to original sources

Human pharmacokinetics of iohexol. A new nonionic contrast medium.

The pharmacokinetics of iohexol, a new nonionic, water-soluble contrast medium, have been determined after intravenous injection in 20 healthy volunteers, at four different dose levels (125-500 mg I/kg). The apparent volume of distribution was 0.27 1/kg, indicating distribution in the extracellular water. The biologic half-life was 121 minutes, comparable with that of other intravascular contrast media. Iohexol was excreted completely unmetabolized in the urine, with a 100% recovery 24 hours after injection. A comparison of iohexol and chromium-51 (51Cr)-EDTA clearances indicates that iohexol is mainly excreted by glomerular filtration. The 51Cr-EDTA clearance was the same when injected separately and concomitantly with iohexol, indicating that glomerular filtration rate is not affected by iohexol. No dose dependency was observed in the investigated parameters t1/2 alpha, t1/2 beta, Vd, ClT or ClR. Iohexol pharmacokinetics are in correspondence with previously reported data on intravascular contrast media.

Adolescent↗

Iohexol in phlebography of the leg. A comparative investigation with meglumine metrizoate.

Comparing iohexol 240 mg I/ml, iohexol 300 mg I/ml and meglumine-Ca metrizoate 200 mg I/ml in phlebography of the leg in patients on or without anticoagulants, no sign of postphlebographic thrombosis was found using the 125I-fibrinogen uptake test and repeat phlebography. More adverse reactions occurred with metrizoate than with iohexol. Metrizoate provided significantly poorer demonstration than the two iohexol concentrations with higher iodine content.

Adult↗

Metrizamide compared with metrizoate in cardioangiography in high-risk patients with coronary artery disease.

In a double-blind, randomized, two-group study of 99 'high-risk' patients mainly with coronary artery disease, the non-ionic contrast medium, Amipaque (metrizamide), was compared with the ionic medium, Isopaque Coronar (meglumine-Na-Ca-metrizoate) in cinecardioangiography. In evaluating the influence of the contrast media on the left ventricular end diastolic pressure (LVEDP), the material was divided into 2 groups, 55 patients with a basal LVEDP of 15 mmHg or less and 44 with an LVEDP above this level. In the former group LVEDP increased significantly after injection of the contrast medium into the left ventricle, but significantly less (p = 0.006) after Amipaque than after Isopaque Coronar. In the patients with a basal LVEDP above 15 mmHg, no significant change occurred in LVEDP after left ventriculography with any of the 2 contrast media. No serious complications occurred.

Adult↗

Adverse reactions following two separate intravascular injections of contrast media in the same patient. A comparison between iohexol and monomeric ionic media.

Adverse reactions following contrast medium injections in 26 non-comparative and parallel trials were extracted from the iohexol vascular clinical trial program in Northern Europe. Six hundred and forty-one patients (13-88 years old) in whom information was available about a vascular contrast medium examination before the iohexol clinical trials were included, enabling a retrospective within patient comparison of adverse reactions. Iohexol gave a lower recurrence frequency (approximately 3.5 times) of reactions than ionic monomers in patients who previously experienced adverse reactions to vascular contrast media. In order to overcome some of the drawbacks with the present retrospective design, prospective comparative studies are recommended.

Adolescent↗

Excretion of iohexol and metrizoate in human breast milk.

Six lactating women undergoing contrast media examination had milk and blood taken to determine the rate and extent of excretion of iohexol (Omnipaque) (four mothers) and metrizoate (Isopaque) (two mothers). Blood samples were taken up to 45 minutes and milk samples up to 48 hours after the contrast medium injection. The excretion was low, reaching a maximum at 3 to 6 hours and showing a slow decay curve (t1/2 = 15 to 108 hours). One mother, who was weaning her baby, showed a different excretion pattern. The amount excreted during 24 hours was about 0.5 per cent of the weight adjusted maternal dose for both iohexol and metrizoate. It is not likely, that such a low dose of poorly absorbed drug would cause any adverse effects in the infant, unless it is hypersensitive to the drug already. The authors consider breast feeding to be acceptable for mothers receiving iohexol or metrizoate.

Adult↗

Summary of U.S. and European intravascular experience with iohexol based on the clinical trial program.

The nonionic contrast medium, iohexol, was released by Nyegaard, Oslo, in 1980 for clinical testing. Results of a three-phase clinical trial program carried out in Europe and the U.S. through December 1983 are summarized. Evaluation of phase I studies of human tolerance and excretion--and phase II studies of effects on pharmacologic and physiologic parameters--indicated that iohexol was well tolerated and effective. Phase III consisted mainly of controlled parallel and crossover studies comparing iohexol with conventional ionic media and with other nonionic agents in a variety of radiographic studies. Image quality was as good or better with iohexol than with ionic media. Iohexol was tolerated significantly better than ionic agents. Patients consistently reported fewer and less intense pain and heat sensations. Iohexol had less effect on blood pressure, blood flow, heart rate, and electrophysiologic parameters, and caused fewer adverse reactions than ionic media for all types of reactions observed.

Clinical Trials as Topic↗