Quantification in Patient Urine Samples of Felbamate and Three Metabolites: Acid Carbamate and Two Mercapturic Acids

PURPOSE: Previously we proposed and provided evidence for the metabolic pathway of felbamate (FBM), which leads to the reactive metabolite, 3-carbamoyl-2-phenylpropion-aldehyde. This aldehyde carbamate was suggested to be the reactive intermediate in the oxidation of 2-phenyl-1,3-propanediol monocarbamate to the major human metabolite 3-carbamoyl-2-phenylpropionic acid. In addition, the aldehyde carbamate was found to undergo spontaneous elimination to 2-phenylpropenal, commonly known as atropaldehyde. Moreover, atropaldehyde was proposed to play a role in the development of toxicity during FBM therapy. Evidence for atropaldehyde formation in vivo was reported with the identification of modified N-acetyl-cysteine conjugates of atropaldehyde in both human and rat urine after FBM administration. Identification of the atropaldehyde-derived mercapturic acids in urine after FBM administration is consistent with the hypothesis that atropaldehyde is formed in vivo and that it reacts with thiol nucleophiles. Based on the hypothesis that the potential for toxicity will correlate to the amount of atropaldehyde formed, we sought to develop an analytic method that would quantify the amount of relevant metabolites excreted in patient urine. METHODS: We summarize the results of an LC/MS method used to quantify FBM, 3-carbamoyl-2-phenylpropionic acid and two atropaldehyde-derived mercapturic acids in the patient population. RESULTS: Analysis was performed on 31 patients undergoing FBM therapy. The absolute quantities of FBM and three metabolites were measured. CONCLUSIONS: This method demonstrated sufficient precision for the identification of patients exhibiting "abnormal" levels of atropaldehyde conjugates and may hold potential for patient monitoring.     

Use of the Code of Ethics for Accountability in Discharge Planning

Nine selected items from the Code of Ethics for nurses are used to illustrate how the code can be used as an excellent resource for accountability with discharge planning. Research findings identify the need for expanded awareness of the code and how to apply it to the discharge planning process. Components of the teaching/learning process are compared to the code to suggest that nurses need increased educational preparation to be accountable for discharge planning.     

The drug lag: an update of new drug introductions in the United States and in the United Kingdom, 1977 through 1987

This report updates previous studies that documented the existence of a significant lag between new drug introductions in the United Kingdom and in the United States. During the 11-year period from 1977 through 1987, the United Kingdom led the United States in the number of first introductions of new drugs (114 versus 41), in average lead time for mutually available drugs (60.7 versus 28.9 months), and in the number of exclusively available drugs (70 versus 54). Analysis by therapeutic category indicated large United Kingdom leads in the introduction of respiratory (5.1 years), cardiovascular (3.2 years), central nervous system (3.2 years), and anti-cancer (2.9 years) agents, and shorter leads for anesthetic and analgesic (2.0 years), gastrointestinal (2.0 years), endocrine (1.4 years), and anti-infective (0.8 years) agents. A comparison of the 5-year period from 1983 through 1987 with the previous 5-year period (1978 through 1982) showed no change in the length of the lag time (1.9 years for each period). These results indicate that the United States continues to lag behind the United Kingdom in the availability of new drugs.