Scintigraphic study of the gastro-intestinal transit and correlations with the drug absorption kinetics of a sustained release theophylline tablet

1 The effects of emesis, gastric lavage and oral activated charcoal on theophylline absorption were compared in healthy volunteers. 2 One of four regimes (ipecacuanha-induced emesis, gas tric lavage, oral activated charcoal and no treatment) was randomly chosen one hour after a simulated over dose with sustained-release theophylline on four sepa rate occasions in twelve healthy volunteers. 3 Syrup of ipecacuanha produced emesis in all twelve volunteers but only seven vomited any tablets. Gastric lavage yielded tablets in only one volunteer. 4 The mean systemic availabilities (areas under the con centration-time curves relative to control) of theo phylline for ipecacuanha-induced emesis, gastric lavage and charcoal, were 107.1%, 101.1% and 16.9%, respectively. 5 Oral activated charcoal was thus highly effective, while gastric lavage and emesis were ineffective in pre venting theophylline absorption. Activated charcoal is potentially the most effective first-line treatment for acute overdosage with sustained-release theophylline tablets.

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Drug Absorption IV: Influence of pH on Absorption Kinetics of Weakly Acidic Drugs

Journal of Pharmaceutical Sciences ◽

10.1002/jps.2600600809 ◽

1971 ◽

Vol 60 (8) ◽

pp. 1160-1163 ◽

Cited By ~ 45

Author(s):

W.G. Crouthamel ◽

G.H. Tan ◽

L.W. Dittert ◽

J.T. Doluisio

Keyword(s):

Drug Absorption ◽

Absorption Kinetics ◽

Acidic Drugs ◽

Influence Of Ph ◽

Kinetics Of

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Physical properties and water absorption kinetics of three varieties of Mucuna beans

Scientific Reports ◽

10.1038/s41598-021-85087-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ajibola B. Oyedeji ◽

Olajide P. Sobukola ◽

Ezekiel Green ◽

Oluwafemi A. Adebo

Keyword(s):

Physical Properties ◽

Water Absorption ◽

Rate Constant ◽

Geometric Mean ◽

Seed Mass ◽

Activation Energies ◽

Mucuna Pruriens ◽

Absorption Kinetics ◽

Kinetics Of ◽

Soaking Temperature

AbstractThe physical properties and water absorption kinetics of three varieties of Mucuna beans (Mucuna pruriens, Mucuna rajada and Mucuna veracruz) were determined in this study. Physical properties including length, width, thickness, geometric mean diameter, sphericity, porosity, bulk density, area, volume and one thousand seed mass were calculated while hydration kinetics was studied by soaking Mucuna beans in water at 30 °C, 40 °C and 50 °C and measuring water uptake at 9 h interval. Peleg’s equation was used to model the hydration characteristics and Arrhenius equation was used to describe the effect of temperature on Peleg’s rate constant k1 and to obtain the activation energies for soaking. Significant variations were observed in almost all the physical properties of the different varieties, however, there were no significant differences (p < 0.05) in their thicknesses and bulk densities. The effectiveness of fit of Peleg’s model (R2) increased with increase in soaking temperature. Peleg’s rate constant k1 decreased with increase in soaking temperature while k2 increased with temperature increase. Activation energies of Mucuna pruriens, Mucuna rajada and Mucuna veracruz were 1613.24 kJ/mol, 747.95 kJ/mol and 2743.64 kJ/mol, respectively. This study provides useful information about the properties of three varieties of Mucuna beans that could be of importance to processors and engineers for process design and optimization.

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Theoretical analysis of water absorption kinetics of recycled aggregates immersed in water

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.124156 ◽

2021 ◽

Vol 302 ◽

pp. 124156

Author(s):

Kun Liang ◽

Yingjie Hou ◽

Jianchun Sun ◽

Xiaoguang Li ◽

Jiahong Bai ◽

...

Keyword(s):

Theoretical Analysis ◽

Water Absorption ◽

Recycled Aggregates ◽

Absorption Kinetics ◽

Kinetics Of

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Comparison of Two Sustained-Release Theophylline Preparations in Adult Patients With Obstructive Airways Disease

The Journal of Clinical Pharmacology ◽

10.1002/j.1552-4604.1985.tb02874.x ◽

1985 ◽

Vol 25 (6) ◽

pp. 444-447 ◽

Cited By ~ 3

Author(s):

Paul S. Harkaway ◽

Paul F. Conlon ◽

John D. Hirsh ◽

William T. Allen

Keyword(s):

Sustained Release ◽

Adult Patients ◽

Sustained Release Theophylline ◽

Obstructive Airways Disease

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Study on the Formaldehyde Adsorption Kinetics of Dry Waters

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.907 ◽

2014 ◽

Vol 809-810 ◽

pp. 907-911

Author(s):

Jun Long Wang ◽

Jie Hou ◽

Ting Jiang ◽

Yong Jun He ◽

Yao Dong Liang

Keyword(s):

Adsorption Kinetics ◽

High Speed ◽

Adsorption Process ◽

Average Diameter ◽

Adsorption Rate ◽

Absorption Kinetics ◽

Order Model ◽

Pseudo Second Order ◽

Kinetics Of ◽

Formaldehyde Adsorption

Dry waters with an average diameter of 82 μm were prepared by a high speed mixed route. The formaldehyde absorption kinetics of dry waters was investigated by simulating indoor formaldehyde pollution in glass chamber. The results showed that pseudo-second order model could be used to simulate the adsorption process; the adsorption rate was highest in the initial 60 minutes; when the adsorption lasted for 180 minutes, the adsorption reached equilibrium.

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Oxygen Absorption Kinetics of Sheets and Films Containing a Commercial Iron-based Oxygen Scavenger

Food Science and Technology International ◽

10.1177/1082013208106207 ◽

2009 ◽

Vol 15 (2) ◽

pp. 159-168 ◽

Cited By ~ 19

Author(s):

M.J. Galotto ◽

S.A. Anfossi ◽

A. Guarda

Keyword(s):

Relative Humidity ◽

Kinetic Parameters ◽

Oxygen Absorption ◽

Absorption Kinetics ◽

Oxygen Scavenger ◽

Arrhenius Behavior ◽

Oxygen Scavengers ◽

Iron Based ◽

Empirical Growth ◽

Kinetics Of

Absorption kinetics of three different forms of the same iron-based oxygen scavenger were studied. Oxygen scavengers were used as pellet, sheet, and film materials. Two scavenger concentrations were used for sheet and film forms. Scavenger samples were analyzed at 75 or 100% relative humidities and stored at 5, 15, and 25°C. Oxygen concentration in the headspace was measured as a function of time. Absorption kinetics was best described by the Chapman-Richards empirical growth model rather than by a first-order reaction. Arrhenius behavior was observed for variations in the final absorption rate with temperature. Absorption capacities, final absorption rates, and activation energies were evaluated and discussed. Scavenger concentration, relative humidity, and temperature effects on kinetic parameters were studied for each experimental condition. Temperature was the most important factor that affected kinetic parameters. At the relative humidity levels studied, any important effect on kinetic parameters was not observed, except on absorption capacities.

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