Cefuroxime axetil is an ester pro-drug which permits the oral administration of cefuroxime. This study was designed to evaluate the dose proportionality of four different doses administered after a meal and to determine the absolute bioavailability of cefuroxime axetil administered with and without food. The study was a six-way randomized crossover trial in 12 normal male volunteers. Subjects received an intravenous dose of cefuroxime (500 mg) and five oral doses of cefuroxime axetil (125, 250, 500-twice, 1000 mg). The intravenous dose and one of the 500 mg doses was administered after an overnight fast. The other four oral doses were administered after a standard meal. Blood samples were collected prior to each dose and serially for 12 h after the dose. Urine was collected for 24 h. Plasma and urine samples were analysed for cefuroxime by high pressure liquid chromatography. There was a linear relationship between the fed dose and both the area under the plasma concentration time curve (r2 = 0.958) and the peak plasma concentration (r2 = 0.943). Based on a comparison of the AUC for the oral and intravenous data, 36 per cent of the fasting and 52 per cent of the fed 500 mg doses were absorbed. The mean peak plasma concentration was 43 per cent greater after the fed dose than the fasting dose. A plot of the mean fraction of unabsorbed drug versus time reveals that absorption is an apparent zero order process from 0.5 to 3 h after dosing.

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A high-affinity transport system that is specific for beta-amino acids has been delineated in rat hearts. This system transports the cardiotonic sulfonic amino acid taurine. beta-Adrenergic stimulation increases the transport capacity without effect on alpha-amino acid uptake, as does stimulation with adenosine 3',5'-monophosphate or theophylline. The existence of such an uptake system for taurine in the heart accounts for the high intra- to extracellular concentration gradient that is maintained, and suggests that cardiac stress is associated with increased taurine uptake. This may explain why taurine is the only amino acid to be markedly elevated in congestive heart failure. Taurine is a modifier of calcium fluxes in the heart, as are beta-adrenergic agonists. The presence of this uptake system suggests a link between beta-adrenergic stimulation of calcium and taurine fluxes.

We evaluated, in a multi-center trial, the safety and efficacy of GR 38032F (GR-C507/75), a novel and selective serotonin antagonist, in preventing acute emesis in chemotherapy-naive patients receiving treatment with regimens containing high-dose cisplatin (greater than or equal to 100 mg/m2). Eighty-five patients were randomized to receive GR 38032F, 0.18 mg/kg, either every six or every eight hours for three doses, beginning 30 minutes before cisplatin. Patients were evaluated for emetic episodes (vomiting or retching) over a 24-hour period following cisplatin. All patients were evaluable for toxicity and 83 were evaluable for efficacy. The overall antiemetic response rate was 75% (55% complete response [CR], 20% major response). No difference in antiemetic control between the two administration schedules was noted. Patients with histories of heavy ethanol use had significantly better antiemetic control (74% CR) than modest or non-drinkers (33% CR). Toxicity of GR 38032F was modest and independent of administration schedule. The most common adverse events included mild hepatic transaminase elevations, self-limited diarrhea, dry mouth, headache, and mild sedation. Our data indicate that GR 38032F is a safe and effective agent in the control of acute cisplatin-induced nausea and vomiting. Additional trials exploring dosing, schedule, and comparison to standard antiemetic agents are indicated.

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