Search PubMedSearch

SEARCH · Search PubMed

Results for “Flufenamic Acid”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Studies of intramolecular rearrangements of acyl-linked glucuronides using salicylic acid, flufenamic acid, and (S)- and (R)-benoxaprofen and confirmation of isomerization in acyl-linked delta 9-11-carboxytetrahydrocannabinol glucuronide.

NMR and HPLC have been used to investigate the rearrangements of 1-O-acylglucuronides in vitro and the occurrence of rearranged isomers in urine. Glucuronides of flufenamic acid, (S)- and (R)-benoxaprofen, salicylic acid, and delta 9-11-carboxytetrahydrocannabinol were synthesized, by use of immobilized enzymes, or purified from urine. Ester-linked isomers of these gluruconides were characterized, and isomers derived from flufenamic acid, (S)-benoxaprofen, and salicylic acid were purified for further study by NMR and HPLC. The positions of the new ester linkages could be identified by two-dimensional NMR. Shifts not only in the resonance of the proton adjacent to the esterified hydroxyl group but also in the resonance of the anomeric proton on carbon 1 of the glucuronic acid moiety could be correlated with the position of each isomeric ester bond. HPLC elution times also correlated with ester position in this small set of samples. The sequences of isomer formation were studied in situ by NMR and also at pH 8 by HPLC. These studies indicate that, for the three cases examined, the C-2 ester is formed first, followed by formation of C-3 and C-4 esters. The purified isomeric esters were found not to re-form the high-energy 1-O-acyl bond. All other rearrangement steps are reversible. In contrast to other glycosides and glycerol esters, no evidence could be found for rearrangements beyond nearest-neighbor hydroxyl groups in glucuronic acid. The sequence of formation and reversibility is consistent with an ortho ester intermediate, as has been proposed for rearrangements of other glycosides.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Oral antipyretic therapy: evaluation of the N-aryl-anthranilic acid derivatives mefenamic acid, tolfenamic acid and flufenamic acid.

The antipyretic activity of three N-aryl-anthranilic acid derivatives, mefenamic acid, tolfenamic acid and flufenamic acid, was compared and their optimal antipyretic dose determined in a trial in 87 children (aged 5 months to 15 years), who suffered from infections and fever exceeding 38.5 degrees C. Tolfenamic acid proved to be the most potent antipyretic agent of the three drugs; it was eight times more powerful than mefenamic acid and three times more powerful than flufenamic acid. The optimal antipyretic doses were: mefenamic acid 4 mg/kg, tolfenamic acid 0.5 mg/kg and flufenamic acid 1.5 mg/kg. It is evident that the antipyretic activity of these anthranilic acid derivatives is even greater than their antirheumatic effect, the difference being most noticeable in the case of tolfenamic acid.

Adolescent

Physical and chemical changes of medicinals in mixtures with adsorbents in the solid state. II. Application of reduced pressure treatment for the improvement of dissolution of flufenamic acid.

Flufenamic acid (FFA) was mixed with magnesium aluminum silicate (MAS) and stored at 60 degrees C at a reduced pressure of about 2.5 mmHg. After storage, when its concentration was not more than 20%, FFA was observed by X-ray diffraction and polarizing microscopy to be amorphous. The dissolution of FFA was thus enhanced in comparison with that of a freshly prepared mixture. Furthermore, the dissolution curves showed a typical supersaturation pattern, and the supersaturation state continued longer, the higher the pH value of the dissolution medium. Flufenamic acid, in a mixture with MAS, became amorphous more rapidly at reduced pressure than at atmospheric pressure, and therefore the effect of improved dissolution appeared earlier at reduced pressure. Infrared spectral studies suggested that FFA, after storage at a reduced pressure with MAS, was dispersed monomolecularly in an ionic form. The technique of treating crystalline medicinals, that have poor solubility in water, with adsorbent at reduced pressure may be useful for improving their dissolution characteristics.

Adsorption

Physical and chemical changes of medicinals in mixtures with adsorbents in the solid state. IV. Study on reduced-pressure mixing for practical use of amorphous mixtures of flufenamic acid.

Flufenamic acid (FFA) was mixed with magnesium aluminum silicate (MAS) at a reduced pressure of about 10 to 50 mmHg employing a commercial mixer for pharmaceutical production. An amorphous state of FFA in the mixture was efficiently achieved with this equipment, and the dissolution of FFA was enhanced in comparison with that of the physical mixture. Effects of the conditions of mixing, such as pressure, temperature and rotating speed, on dissolution of FFA were determined. Through stability tests at 40 degrees C under both dry and humid conditions, no change in dissolution profiles was recognized in a 5% FFA mixture stored under any conditions. On the other hand, decreases in dissolution behavior were observed in 10% and 20% FFA mixtures when they were stored under humid conditions. These results suggested that humidity should be avoided during the storage of amorphous mixtures of FFA with MAS for production purposes.

Adsorption

The bioavailability of flufenamic acid from aluminum flufenamate tablet and flufenamic acid capsule, and the influence of food and aluminum hydroxide gel.

The bioavailabilities of flufenamic acid (I) from a commercial aluminum flufenamate (II) tablet and I capsule were estimated by measuring urinary excretion of I and its metabolites fluorometrically. The dissolution rates of I from both dosage forms were also determined. The effects of concomitant intake of food or antacid on the bioavailabilities from the II tablet and the I capsule were investigated. The extent on I bioavailability from the II tablet was less than 30% of that from the I capsule. Dissolution tests suggested that the low bioavailability of I from II tablet resulted from the extremely slow release of I from the II complex. Intake of a standard meal retarded I absorption from I capsule, but did not affect that from the II tablet. Ingestion of dried aluminum hydroxide gel granules had little effect on I bioavailability from the I capsule.

Adult

The influence of acetylsalicylic acid, phenylbutazone, indomethacin, and flufenamic acid on the kinetics of leucocytes during acute inflammation.

Five groups of ten male Wistar rats each were used for the purpose of this experiment. All subjects suffered from sterile acute inflammation in the peritoneal cavity. A sterile beef heart infusion broth reinforced with proteose-peptone was injected to cause the inflammation. The following substances mixed with tragacanth gum were given orally at in 12 h intervals: --Acetalsalicylic acid 150 mg/kg body weight to the first group; --Phenylbutazone 100 mg/kg body weight to the second group; --Indomethacin 15 mg/kg body weight to the third group; --Flufenamic acid 100 mg/kg body weight to the fourth group. Finally the fifth group received only tragacanth gum. The rats were sacrificed after 48 hours and leucocytes were collected from the peritoneal cavity by washing with 5 ml 0.9% NaCl solution. The total leucocyte number and the percent of each type were estimated for each group individually. A statistically significant decrease in the number of leucocytes migrated to the peritoneal cavity due to the inflammation was observed in rats that received one of the drugs (group I to IV) when compared to rats that received only the excipient (group V). Likewise, significant differences were noted in the composition of each type.

Analgesics

Niflumic and flufenamic acids are potent reversible blockers of Ca2(+)-activated Cl- channels in Xenopus oocytes.

The effects of niflumic acid and flufenamic acid, two nonsteroidal anti-inflammatory agents known to block anion transport in red blood cells, on Ca2(+)-activated Cl- currents (ICl(Ca)) in Xenopus oocytes were examined. Both compounds reversibly inhibited ICl(Ca), elicited in response to depolarizing voltage steps, in a dose-dependent manner, with no effect on the shape of the current-voltage curve. The apparent inhibition constant for niflumic acid was 17 microM, whereas that for flufenamic acid was 28 microM. Niflumic acid also inhibited ICl(Ca) elicited by bath application of Ca2+ to oocytes permeabilized using the Ca2+ ionophore A23187, demonstrating that the inhibition of ICl(Ca) is due to a direct interaction with the Cl- channel, rather than by interference with Ca2+ entry through voltage-dependent Ca2+ channels. In addition to their use in the elimination of ICl(Ca) as a possible source of artifact when Xenopus oocytes are used as an expression system for exogenous ion channels and receptors, it is expected that these two compounds will find use as potent anion channel blockers.

Animals

Pharmacokinetics of flufenamic acid in man.

Flufenamic acid (200 mg) was administered in the form of a soft capsule to 8 young healthy volunteers after an overnight fast. The drug was absorbed irregularly and plasma curves showed large variation. Peak plasma concentrations varied strongly (6-20 micrograms/ml) but were usually reached within 1.5 h. The terminal elimination half-life is long (5-22 h) and the total body clearance is low (80-150 ml/min) causing long mean residence time (4-28 h). The total apparent volume of distribution is much larger than the total body water volume. The large intersubject variations led to the conclusion that mean values of the pharmacokinetic parameters of flufenamic acid after oral administration are not useful for practical purposes.

Administration, Oral

Niflumic and flufenamic acids are potent inhibitors of chloride secretion in mammalian airway.

Effects of niflumic acid (NFA) and flufenamic acid (FFA), the two nonsteroid anti-inflammatory agents recently reported to inhibit Cl- current in Xenopus oocytes, were examined in cultured monolayers of dog and cow trachea. Both agents showed potent inhibition to the short-circuit current (Isc), an index of magnitude of transepithelial Cl- secretion, with values of Ki of 0.02 (for NFA) and 0.06 (for FFA) mM, respectively. The sensitivity sequence of Isc to the Cl- channel inhibitors tested was NFA > FFA > diphenylamine-2-carboxylate (DPC) >> anthracene-9-carboxylate (A9C). Thus, NFA and FFA are so far the most potent commercially available Cl- channel inhibitors tested in Cl(-)-secreting epithelia. The sensitivity sequence of 36Cl uptake to the above Cl- channel inhibitors in Xenopus laevis oocytes was found to be identical to the cultures of trachea. This seems to imply that the membrane Cl- channels of Xenopus oocytes are functionally similar to that identified in mammalian Cl(-)-secreting epithelia.

Animals

Interaction of the non-steroidal anti-inflammatory drug flufenamic acid with gastric acid secretion and H+/K(+)-ATPase.

1. The effects of the non-steroidal anti-inflammatory drug (NSAID) flufenamic acid on H+ production in isolated and enriched guinea-pig parietal cells and on H+/K(+)-ATPase activity in ion-tight inside-out membrane vesicles from pig gastric mucosa were studied. 2. At low concentrations (0.1 and 1.0 mumol/L), flufenamic acid increased the secretory response of parietal cells to dibutyryl cyclic AMP (dbcAMP). At higher concentrations (10 and 100 mumol/L) it progressively inhibited basal and dbcAMP-stimulated acid production. 3. Flufenamic acid (10 mumol/L) increased K+ (0.5-10.0 mmol/L) and K+ (0.5-1.0 mmol/L) plus gramicidin-stimulated ATPase activity in gastric membrane vesicles. The Km value for K+ (1.6 and 1.0 mmol/L in the absence and presence of gramicidin, respectively) was decreased to 0.8 and 0.5 mmol/L, respectively. At higher concentrations (greater than or equal to 50 mumol/L), flufenamic acid inhibited K+ plus gramicidin-stimulated ATPase activity (inhibited concentration at 50% [IC50] = 186 mumol/L) and reduced the proton concentration (IC50 = 50 mumol/L). 4. It is concluded that flufenamic acid-induced enhancement of dibutyryl cyclic AMP-stimulated H+ production in the parietal cell reflects the stimulation of H+/K(+)-ATPase. We suggest that activation of the enzyme involves increased affinity of K+ towards the K(+)-binding site of the enzyme and/or increased KCl permeability at the vesicle membrane. The inhibitory action of the drug on H+ production in parietal cells results from a detergent and/or protonophoric-like action at the apical parietal cell membrane, and from inhibition of H+/K(+)-ATPase activity.

Adenosine Triphosphatases

Inhibition of prostaglandin synthetase and carrageenan-induced edema by tricyclic analogs of flufenamic acid.

A group of tricyclic analogs of flufenamic acid were tested for their ability to inhibit both the biosynthesis of prostaglandin and carrageenan-induced inflammation of the rat paw. All had activity greater than phenylbutazone as inhibitors of prostaglandin synthetase, with SK&F 22908 being as active as flufenamic acid. The anti-inflammatory activities of these compounds correlated only to a minor degree with the inhibition of prostaglandin biosynthesis. The data support the position that within this series of compounds inhibition of prostaglandin synthetase and non-steroidal antiinflammatory activity, as well as ulcerogenic liability, may be an expression of different mechanisms.

Animals

Percutaneous absorption of flufenamic acid in rabbits: effect of dimethyl sulfoxide and various nonionic surface-active agents.

Eight nonionic surface-active agents were each incorporated at a concentration of 10% into a white petrolatum ointment base containing 10% flufenamic acid with or without dimethyl sulfoxide. Percutaneous absorption was studied by determining the plasma concentration of flufenamic acid in New Zealand White rabbits at regular intervals for 8 hr following application of the ointment. The percutaneous absorption of flufenamic acid was significantly increased when sorbitan trioleate, polyoxyl 8 stearate, or polyoxyethylene 2 oleyl ether were added to the ointment containing flufenamic acid and white petrolatum. The percutaneous absorption of flufenamic acid was increased significantly when sorbitan monopalmitate, sorbitan trioleate, polyoxyl 8 stearate, polyoxyethylene 20 cetyl ether, or polyoxyethylene 2 oleyl ether were added to the ointment containing dimethylsulfoxide, flufenamic acid, and white petrolatum.

Animals