PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 1764870

Omeprazole drug interaction studies.

T Andersson
View original source ↗Export metadata ↓

Abstract

This review examines the literature on drug interactions with omeprazole. Different mechanisms have been proposed as potential causes for such interactions. First, the absorption of some drugs might be altered due to the decreased intragastric acidity resulting from omeprazole treatment. There was no effect of omeprazole on the absorption of amoxycillin, bacampicillin and alcohol, while the amount of digoxin and nifedipine absorbed was increased by 10 and 21%, respectively, both increases probably being of no clinical significance. Secondly, the metabolism of high clearance drugs might be altered by changes in liver blood flow, although that is not affected by omeprazole, as indicated by the unchanged elimination of indocyanine green. In addition, the clearance of intravenously administered lidocaine (lignocaine) [a high clearance drug] was unaffected by omeprazole, further indicating that the latter does not alter liver blood flow. Thirdly, since omeprazole is a substituted benzimidazole, it might have the potential to interfere with the metabolism of other drugs by altering the activity of drug metabolising enzymes in the cytochrome P450 system, through either induction or inhibition. There is no indication of induction of this enzyme system in any interaction study with omeprazole. As regards inhibition, on the other hand, there is now considerable information available which indicates that omeprazole has the potential to partly inhibit the metabolism of drugs metabolised to a great extent by the cytochrome P450 enzyme subfamily IIC (diazepam, phenytoin), but not of those metabolised by subfamilies IA (caffeine, theophylline), IID (metoprolol, propranolol) and IIIA (cyclosporin, lidocaine, quinidine). Since relatively few drugs are metabolised mainly by IIC compared with IID and IIIA, the potential for omeprazole to interfere with the metabolism of other drugs appears to be limited.

Explore related subjects

AbsorptionBiomarkersCytochrome P-450 Enzyme SystemDrug InteractionsHumansLiver CirculationOmeprazolePharmaceutical PreparationsJournal ArticleReview

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

T Andersson. 1991. Omeprazole drug interaction studies.. https://doi.org/10.2165/00003088-199121030-00004

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Adsorption, absorption, and biological degradation of ammonia in different biofilter organic media.

A tailor-made apparatus called ammoniometer, which is a batch mode respirometer applied to the study of ammonia biodegradation in biofilter media, has been used to evaluate adsorption, absorption, and biodegradation in five different organic materials (compost, coconut fibre, bark, pruning wastes, and peat) obtained from full-scale biofilters in operation in several waste treatment plants. The results showed that absorption could be represented by a Henry's law linear equation, with values of the Henry coefficient significantly higher (from 1,866 to 15,320) than that of pure water (1,498). Adsorption data were successfully fitted to Langmuir and Freundlich isotherms and maximum adsorption capacity varies from 1.06 to 1.81 mg NH(3)/g dry media. Ammonia biodegradation rates for each organic material were also calculated. Biodegradation rates varied from 0.67 to 7.82 mg NH(3)/kg media/d depending on the material tested. The data obtained showed important differences in the behaviour of the biofilter organic media, which has important implications in the design and modelling of these systems.

Absorption↗
PubMed2007

The use of an oil absorber as a strategy to overcome starvation periods in degrading 1,2-dichloroethane in waste gas.

This work investigates the use of an oil absorber as an operational strategy in vapor phase bioreactors exposed to starvation periods, during the treatment of inhibitory pollutants. After being exposed to 1,2-dichloroethane (DCE) starvation periods, the response and stability of a combined oil-absorber-bioscrubber (OAB) system was compared to that of a bioscrubber only (BO) system. In the BO system, after a 5.2 days starvation period, the DCE removal efficiency was reduced to 12%, and 6 days were needed to recover the initial removal efficiency when the DCE feed resumed. The total organic discharged (TOD(DCE)) was 16,500 g(DCE) m(bioscrubber) (-3) after the DCE starvation. Biomass analysis performed using fluorescence in situ hybridisation (FISH) showed that the microbial activity was significantly reduced during the starvation period and that 5 days were needed to recover the initial activity, after the re-introduction of DCE. In contrast, the performance of the OAB system was stable during 5.2 days of DCE starvation. The DCE removal efficiency was not affected when the DCE feed resumed and the TOD(DCE) was significantly reduced to 2,850 g(DCE) m(bioscrubber) (-3). During starvation, the activity of the microbial culture in the OAB system showed a substantially lower decrease than in the BO system and recovered almost immediately the initial activity after the re-introduction of DCE. Additionally, a mathematical model describing the performance of the OAB system was developed. The results of this study show that the OAB system can effectively sustain the biological treatment of waste gas during starvation periods of inhibitory pollutants.

Absorption↗
PubMed2007

Pterin pigment granules are responsible for both broadband light scattering and wavelength selective absorption in the wing scales of pierid butterflies.

A small but growing literature indicates that many animal colours are produced by combinations of structural and pigmentary mechanisms. We investigated one such complex colour phenotype: the highly chromatic wing colours of pierid butterflies including oranges, yellows and patterns which appear white to the human eye, but strongly absorb the ultraviolet (UV) wavelengths visible to butterflies. Pierids produce these bright colours using wing scales that contain collections of minute granules. However, to date, no work has directly characterized the molecular composition or optical properties of these granules. We present results that indicate these granules contain pterin pigments. We also find that pterin granules increase light reflection from single wing scales, such that wing scales containing denser granule arrays reflect more light than those with less dense granule collections. As male wing scales contain more pterin granules than those of females, the sexual dichromatism found in many pierid species can be explained by differences in wing scale pterin deposition. Additionally, the colour pattern elements produced by these pterins are known to be important during mating interactions in a number of pierid species. Therefore, we discuss the potential relevance of our results within the framework of sexual selection and colour signal evolution.

Absorption↗