Phenytoin and phenobarbital concentrations in serum: a comparison of Ames Seralyzer with GLC, TDX, and EMIT

A recently developed system for measuring antiepileptic drug concentrations was evaluated for phenytoin and phenobarbital. The apoenzyme reactive immunoassay system was compared with gas-liquid chromatography, EMIT, and TDX systems. Comparisons were performed with control specimens and with sera obtained from patients at three facilities. Precision for all methods was similar, with within-run and between-run coefficients of variation generally 5%. The accuracy of all methods was acceptable, but bias was present in some. However, measurements obtained by a nontechnical person (physician) in a clinical setting were sometimes inaccurate.     

Retrospective database analysis on the effectiveness of typical and atypical antipsychotic drugs in an outpatient clinic setting

OBJECTIVE: To report the outcomes of a retrospective database analysis to compare the effectiveness of atypical and typical antipsychotic drugs. METHODS: Medical records of patients admitted to the psychiatry outpatient clinic between January 1998 and October 2005 were retrospectively reviewed. Data obtained from patient records were noted on a special form assessing four aspects of the treatment history: socio-demographic features, disease characteristics, initial treatment at the time of admission, and course of treatment. Patient groups (typical/atypical and Risperidone/Haloperidol/Olanzapine) were compared for time to all-cause medication discontinuation and rate of discontinuation. RESULTS: There was no statistically significant difference in the duration of treatment between patients using atypical (n = 150) and typical (n = 124) antipsychotics. The duration of treatment was significantly longer in patients on Haloperidol (n = 91) compared with those on Risperidone (n = 63). Rates of discontinuation over 18 months were 59.3% for patients on atypical antipsychotics and 57.3% for those on typical antipsychotics, and 68.3% for patients on Risperidone, 51.6% for patients on Haloperidol and 54.3% for patients on Olanzapine. CONCLUSION: Despite our hypothesis patients with chronic schizophrenia discontinued their atypical and typical antipsychotics, at a high rate with no significant difference indicating substantial limitations in the effectiveness of these drugs.     

Medication reconciliation by clinical pharmacists in an outpatient family medicine clinic

ObjectivesTo evaluate the incidence of medication discrepancies in electronic health record (EHR) medication lists in an outpatient family medicine clinic where clinical pharmacists perform medication reconciliation, to classify and resolve the discrepancies, to identify the most common medication classes involved, and to assess the clinical importance of the discrepancies.MethodsThis research was conducted at Bethesda Family Medicine Clinic in St. Paul, MN, with data collected from February 2009 to February 2010. To be included, patients had to be 18 years or older and have at least 10 medications listed in the EHR. The clinical pharmacist saw each patient before the physician, reviewed the medication list with the patient, and made corrections to the EHR medication list. When possible, comprehensive medication management (CMM) also was conducted.ResultsDuring 1 year, 327 patients were seen for medication reconciliation. A total of 2,167 discrepancies were identified and resolved, with a mean (±SD) of 6.6 ±  total discrepancies and 3.4 ±  clinically important discrepancies per patient. The range of total discrepancies per patient was 0 to 26. The most common discrepancy category was “patient not taking medication on list” (54.1%). Overall, the source of the discrepancy usually was the patient, but it varied according to discrepancy category. The most common medication classes involved were pain medications, gastrointestinal medications, and topical medications. Of the 2,167 discrepancies, 51.1% were determined to be clinically important by the pharmacist. The pharmacist conducted CMM in 48% of patients.ConclusionOutpatient medication reconciliation by a pharmacist identified and resolved a large number of medication discrepancies and improved the accuracy of EHR medication lists. Because more than 50% of the discrepancies were thought to be clinically important, improving the accuracy of medication lists could affect patient care.     

Phenytoin and phenobarbital protein binding alterations in a uremic burn patient

A case is reported in which dramatic decreases in the protein binding of phenytoin and phenobarbital were noted. A 57-year-old burn patient with a history of a seizure disorder had increased free fractions of phenytoin and phenobarbital. The patient later developed renal failure and the free fractions of both drugs were further increased. Decreases in the protein binding of phenytoin in patients with hypoalbuminemia and/or uremia have been well documented, but the effects of these conditions on phenobarbital protein binding have not been well studied. In the case described here, the presence of both hypoalbuminemia and uremia were necessary before a doubling of the free fraction of phenobarbital was noted. Although it is not a highly protein-bound drug, in some circumstances protein binding alterations of phenobarbital may be of clinical significance.     

Therapeutic drug monitoring of escitalopram in an outpatient setting

The main objectives of this study were to outline the inter- and intraindividual and overall pharmacokinetic variability of S-citalopram, S-desmethylcitalopram, and S-didesmethylcitalopram in serum by means of therapeutic drug monitoring; and to investigate potential correlations between the serum concentration and simultaneously collected clinical data. The study was conducted on outpatients in Sweden in 2002 to 2005. Included in the pharmacokinetic evaluation were 155 patients (68% women and 32% men) aged 17 to 95 years (average, 51 years). One serum sample per patient, taken as a trough value in steady state, was assessed. For the inter- and intraindividual variation calculation, 16 patients were included with two eligible samples each. The median daily dose was 20 mg/day (range, 5-40 mg). Extensive overall serum concentration variability was seen for all dose levels. The interindividual coefficient of variation for dose-normalized concentrations was 71% for S-citalopram, 36% for S-desmethylcitalopram, and 50% for S-didesmethylcitalopram. The intraindividual variations over time for the same parameters were approximately 30%, except for the ratio S-desmethylcitalopram/S-citalopram, which was 23%. The median S-desmethylcitalopram level was approximately 60% of the parent substance and the S-didesmethylcitalopram level approximately 9%. Higher age was correlated with higher serum concentrations, but no gender-related concentration differences were found. A majority (76%) of the patients took one or more drugs in addition to escitalopram, but concomitant medication did not seem to interact with escitalopram. However, women taking oral contraceptives showed a lower metabolic ratio compared with age-matched women. As a result of the wide range of the ratio in this population, these findings are not considered of clinical relevance.     

Combination therapy with carbamazepine and valproic acid in problem cases at an outpatient epilepsy clinic

A total of 64 problem patients with epilepsy (42 retrospective evaluations, 22 prospective cases) was treated with the combination of carbamazepine and valproic acid. Most frequent seizure types were tonic clonic (focal origin or primarily generalized), complex partial ones, and absences. Best results were observed in patients with tonic clonic seizures in contrast to complex partial ones. The pattern of adverse reactions (none of significant severity) was according to those of monotherapies with the compounds. In cases with relevant improvement serum levels of carbamazepine and valproic acid were within the range commonly described for monotherapies.     

Dietary choices and likelihood of abstinence among alcoholic patients in an outpatient clinic

Animal experimentation and informal clinical observation both suggest a possible relation between diet and drinking. Sixty-four newly sober out-patients at the Elmhurst Alcoholism Treatment Program were interviewed at each clinic visit using the 24-h dietary recall method. Patients were interviewed an average of 3 times each. We analyzed for calories, carbohydrates, sucrose, sugar added to beverages, protein, fats, vitamins and minerals. Patients were grouped according to the number of days they remained sober from their last drink. Those who stayed sober longer chose diets containing twice as much sugar added to beverages and more overall carbohydrates (P less than 0.05). At this time we cannot say whether longer sobriety increased appetite for sugar or whether the choice of sugar influenced the patients' ability to stay sober.