ABSTRACT
The plasma concentration-time profiles and pharmacokinetics were characterized for nicotine and its major metabolite, cotinine, after multiple daily application of a nicotine user-activated transdermal therapeutic system (UATTS) to nine healthy smokers. The volunteers abstained from smoking 24 hr prior to and during the course of the study. A 10-cm2 system (designed to deliver 75 micrograms/cm2/hr) was applied every 24 hr for 5 days, with serial blood samples taken on Days 1 and 5 and after system removal on Day 5. Generally, the nicotine UATTS was well tolerated. Predose nicotine concentrations on Days 3 to 5 indicated that steady state was reached by Day 3. The nicotine pharmacokinetic parameters for Day 1 and Day 5 were similar: the mean (SD) AUC(0-24) values for Days 1 and 5 were 271.7 (50.7) and 311.7 (55.0) ng.hr/ml, the mean (SD) Cmax values were 16.3 (2.6) and 16.8 (2.9) ng/ml, and the median (range) Tmax values on Days 1 and 5 were 12 (9-24) hr and 12 (0-24) hr, respectively. There was only slight or no accumulation of nicotine after multiple dosing as indicated by the Day 5 to Day 1 AUC and Cmax ratios of 1.15 (0.09) and 0.98 (0.06), respectively. Overall, the UATTS system maintained relatively constant plasma nicotine concentrations and is suitable for once-daily application.
Subject(s)
Nicotine/pharmacology , Smoking/metabolism , Administration, Cutaneous , Adult , Cotinine/pharmacokinetics , Drug Administration Schedule , Humans , Male , Nicotine/administration & dosageABSTRACT
The method described for determining NO3- in dried foods is based on extraction of NO3- from the sample with subsequent nitration of benzene. The nitrobenzene is extracted with ethyl acetate, analyzed by using a gas chromatograph-thermal energy analyzer (GC-TEA), and quantitated against a nitrobenzene standard. Sensitivity is 100-200 micrograms/kg. Coefficients of variation for analyses of dried foods were 3-13%. Recovery of NO3- from nonfat dry milk spiked at 10 mg/kg averaged 100%.
Subject(s)
Food Analysis/methods , Nitrates/analysis , Chromatography, Gas/methods , Dairy Products/analysis , Food Preservation , Hot Temperature , Infant Food/analysisABSTRACT
Several drugs known to affect prostaglandin synthesis, release, or metabolism have been tested for their effects on ovum transport in the rabbit after systemic or local administration. Acceleration of transport was obtained with several drugs; among the most effective were benzydamine, a blocker of thromboxane production, and L11204, an inhibitor of prostaglandin metabolism.
