Furosemide displacement

Not understood. One suggestion is that furosemide displaces trichloroacetic acid (the metabolite of cloral hydrate) from its protein binding sites, which in its turn displaces levothyroxine or alters the serum pH so that the levels of free levothyroxine rise leading to a hypermetabolic state. ... 

Diuretic activity can be retained in the face of replacement of one of the sulfonamide groups by a carboxylic acid or amide. Reaction of the dichlorobenzoic acid, 174, with chlorsulfonic acid gives the sulfonyl chloride, 175 this is then converted to the amide (176). Reaction of that compound with furfuryl ine leads to nucleophilic aromatic displacement of the highly activated chlorine at the 2 position. There is thus obtained the very potent diuretic furosemide (177). ... 

W. Groskopf, B. Green, L. Sohn, and S. Hsu, Furosemide as a displacing agent in assay of total triiodothyronine, Clin. Chem. 37, 587-588 (1991). 

Kraak et al. (38) reported the first ACE application to study drug binding to a plasma protein. They used the model system warfarin-human serum albumin (HSA) to compare the suitability of the Hummel-Dreyer, frontal analysis, and vacancy peak methods. A more methodologically intended paper from Erim and Kraak (39) used VACE to study the displacement of warfarin from bovine serum albumin (BSA) by furosemide and phenylbutazone. They concluded that VACE is especially suited to examining competitive properties of simultaneously administered compounds toward a given protein-drug system. 

Displacement of T3 and T4 from TBG with transient hyperthyroxinemia Salicylates, fenclofenac, mefenamic acid, furosemide... 

Ultrafiltration has been used to determine the protein bound fraction of many drags, such as methadone (Wilkins et al. 1997), phenylacetate and phenylbu-tyrate (Boudoulas et al. 1996), etoposide (Robieux et al. 1997), doxorubicin and vincristine (Mayer and St-Onge 1995), disopyramide (Echize et al. 1995), and ketamine and its active metabolites (Hijazi and Boulieu 2002). Schumacher et al. (2000) have shown the applicability for the determination of erythro-cyte/plasma distribution. The method of UF has been applied in the measurement of free unaltered thyroxin or after displacement by salicylate as well after displacement by heparin in healthy people and in patients with non-thyroidal somatic illness (Faber et al. 1993). The protein binding of tritium labeled, antidiabetic repaglinide and its displacement by warfarin, furosemide, tolbutamide, diazepam, glibenclamide and nicardipine were determined by ultrafiltration (Plumetal. 2000). 

Displacement of bilirubin from its albmnin bond. Various endogenous substances (e. g. long-chain fatty acids and bile acids) or exogenous compounds (e. g. medication, such as ampicillin, ajma-line, quinidine, furosemide, indomethadn, probenecid, rifampicin, sulphonamide etc., and X-ray contrast media) can compete with bilirubin, not only with respect to its specific binding site, but also for its carrier protein. 

Dichloro-5-sulphamoyl benzoic acid may be prepared by reacting 2,4-dichlorobenzoic acid with chlorosulphonic acid at an elevated temperature and then carrying out the amidation. This on treatment with furfuryl amine in the presence of sodium bicarbonate, affords nueleophilie aromatie displacement of the highly activated chlorine at C-2, thereby yielding furosemide. However, the proteetion of the chlorine atom at C-4 may be achieved by regulating the temperature of the furfuiylamination. 

Displaces warfarin from plasma protein binding sites. Reduces natriuretic and diuretic effects of furosemide and antihypertensive effects of thiazides, beta blockers, prazosin, and captopril. 

Drug interactions like other NSAIDs, plasma protein binding of ketorolac is extensive, leading to potential drug interactions due to displacement of other highly protein-bound drugs. Concurrent use of probenicid with ketorolac will decrease its elimination. Concurrent use of furosemide with ketorolac will decrease the diuretic s effect. Concurrent administration of other NSAIDs may increase plasma levels of ketorolac. 

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