Search PubMed⌕ Search

Biomedical subjects

J S Markowitz

Publications and source records attributed to J S Markowitz.

At least 19 recordsLinked to original sources

New onset diabetes and atypical antipsychotics.

As a class, the atypical antipsychotics are the first line treatment choice for the psychopharmacologic management of psychotic disorders. Emerging evidence currently suggests that at least two of the atypical antipsychotics, clozapine and olanzapine, and possibly quetiapine may be associated with the risk of new onset diabetes or serum glucose dyscontrol. Computerized Medline and Current Contents searches from years 1966 through June 2000 were undertaken to retrieve all pertinent studies and case reports of typical and atypical antipsychotics and glucose-insulin problems. Historically, both schizophrenia and the older antipsychotics medications have been reported to be associated with a similar risk for causing disruptions in serum glucose control. Additionally, diabetes has well recognized associations with a number of medical disorders such as cardiovascular disease; it is therefore worthy of attention. Hypothesized mechanisms for antipsychotic induced diabetes ranges from the antagonism of several neurotransmitter receptors to insulin resistance. A total of thirty-five cases of induced or exacerbated diabetes are presently available in the published literature; the vast majority of cases implicate clozapine (n=20) and olanzapine (n=15). In multiple cases, diabetic ketoacidosis has been the presenting symptom; daily atypical antipsychotic doses have been within acceptable ranges and were not considered to be excessive.

Adult↗

A double-blind placebo-controlled case study of the use of donepezil to improve cognition in a schizoaffective disorder patient: functional MRI correlates.

Cognitive impairment in multiple domains is common in patients with schizophrenia and may be a powerful determinant of poor functional ability and quality of life. We report a double-blind, placebo-controlled, cross-over study of donepezil augmentation in a schizoaffective disorder patient stabilized on olanzapine pharmacotherapy. The patient showed significant improvements in several cognitive measures and increased activation of prefrontal cortex and basal ganglia on functional MRI during the donepezil augmentation. In addition, the donepezil augmentation resulted in a reduction of depressive symptoms and in significant improvements in functional abilities and quality of life. Further studies of donepezil augmentation of neuroleptics in schizophrenia are warranted.

Adult↗

Effect of St. John's wort (Hypericum perforatum) on cytochrome P-450 2D6 and 3A4 activity in healthy volunteers.

The effects of the herb St. John's wort (Hypericum perforatum), a purported antidepressant, on the activity of cytochrome P-450 (CYP) 2D6 and 3A4 was assessed in seven normal volunteers. Probe substrates dextromethorphan (2D6 activity) and alprazolam (3A4 activity) were administered orally with and without the co-administration of St. John's wort. Urinary concentrations of dextromethorphan and dextrorphan were quantified and dextromethorphan metabolic ratios (DMRs) determined. Plasma samples were collected (0-60 hrs) for alprazolam pharmacokinetic analysis sufficient to estimate tmax, Cmax, t 1/2, and AUC. Validated HPLC methods were used to quantify all compounds of interest. No statistically significant differences were found in any estimated pharmacokinetic parameter for alprazolam or DMRs. These results suggest that St. John's wort, when taken at recommended doses for depression, is unlikely to inhibit CYP 2D6 or CYP 3A4 activity.

Adult↗

Oral nutritional supplementation for the alcoholic patient: a brief overview.

Approximately 1.5 million Americans seek treatment for alcoholism annually. Malnutrition is frequently observed in the alcoholic population due to several factors, including poor dietary intake, alcohol-associated gastrointestinal problems, decreased nutrient absorption and enhanced excretion of trace elements. The administration of multivitamins with minerals and folic acid is commonplace. The present paper reviews basic nutrient deficits commonly encountered in alcoholic individuals and describes the rationale and basic guidelines for oral replacement therapy.

Administration, Oral↗

Successful liver transplantation in a patient with Budd-Chiari syndrome caused by homozygous factor V Leiden.

Budd-Chiari syndrome (BCS) is a rare form of portal hypertension characterized by hepatic venous outflow obstruction. Although hematologic disorders are the most common cause of this syndrome, to date, 30% of the cases have been classified as idiopathic. Resistance to activated protein C caused by factor V Leiden is the most common cause of thrombophilia; its role in the pathogenesis of BCS is now becoming apparent. We report successful liver transplantation in a patient with BCS caused by homozygous factor V Leiden. The patient was administered standard heparin anticoagulation until activated protein C resistance was normalized by the liver allograft. Liver transplantation corrected the thrombophilic state. The patient has excellent graft function, is not on anticoagulation therapy, and has had no recurrent venous thrombosis at 5 months posttransplantation. Activated protein C resistance caused by the factor V Leiden mutation may be responsible for idiopathic cases of BCS. To avoid unnecessary long-term anticoagulation after liver transplantation, factor V Leiden should be considered as a pathogenic factor in BCS. In addition, because of the high prevalence of factor V Leiden in the world population, cadaveric organ donors with a history of venous thrombosis should be screened for activated protein C resistance lest thrombophilia be transmitted to the recipient.

Adult↗

Single-dose pharmacokinetics of methylphenidate in CYP2D6 extensive and poor metabolizers.

Six adults phenotyped as either extensive (N = 4) or poor (N = 2) metabolizers for cytochrome P450 (CYP) 2D6 were given a 10-mg oral dose of methylphenidate (MPH) on two separate occasions with and without quinidine, a potent CYP2D6 inhibitor. Quinidine had no significant effect on the pharmacokinetics of either MPH or ritalinic acid, its major metabolite, in either group of CYP2D6 metabolizers. These data suggest a lack of involvement of CYP2D6 in the metabolism of MPH. Drugs that are inhibitors of CYP2D6 when taken concurrently with MPH should not affect its plasma concentration.

Adolescent↗

An assessment of selective serotonin reuptake inhibitor discontinuation symptoms with citalopram.

The selective serotonin reuptake inhibitors (SSRIs) have recently been associated with a variety of somatic and psychiatric symptoms upon abrupt drug discontinuation. These symptoms have been variously termed SSRI withdrawal, or SSRI discontinuation syndrome. Although all of the available SSRIs have been reported to cause discontinuation symptoms, some appear to have a greater propensity to cause these adverse events than others. Data from a previously completed placebo-controlled, double-blind study designed to assess citalopram in depression relapse prevention were analysed to assess patients for the emergence of discontinuation effects following randomization to placebo after 8 weeks of active drug treatment. Side-effects that occurred during the first 2 weeks following randomization to active drug (n = 150) or placebo (n = 72) were measured using the UKU unwanted side-effect list. The proportion of patients that experienced one or more events over the 2-week period following randomization was similar in the two groups, and there was no association between citalopram dose prior to randomization and the reporting of symptoms. Most of the events that did occur were mild in intensity and none resulted in discontinuation from the study. Events occurring at a higher frequency in the placebo group were most associated with the central nervous system (CNS). These events may reflect a re-emergence of depressive symptoms, since only 14.8% of patients randomized to placebo who did not relapse experienced CNS events, a low symptom incidence that was non-significant (P = 0.562) compared to patients continuing treatment (10.9%). Therefore, this assessment suggests that any symptoms associated with rapid discontinuation of citalopram are mild and transient, and emphasizes the significant role re-emerging depression and / or anxiety may play in the assessment and identification of SSRI discontinuation symptoms.

Citalopram↗

Avoiding psychotropic drug interactions in the cardiovascular patient.

Recent advances in our understanding of the hepatic cytochrome P450 inhibitory effects of the newer antidepressants have increased concern about drug interactions in the practice of psychiatry. The authors summarize the potential interactions of psychoactive drugs with cardiovascular medications. Practicing psychiatrists encounter many patients with cardiovascular disease, and an awareness of these interactions will improve knowledgeable prescribing for medically ill patients with comorbid mental disorders.

Cardiovascular Agents↗

Ethylphenidate formation in human subjects after the administration of a single dose of methylphenidate and ethanol.

Ethylphenidate was recently reported as a novel drug metabolite in two overdose fatalities where there was evidence of methylphenidate and ethanol coingestion. This study explores the pharmacokinetics of ethylphenidate relative to methylphenidate and the major metabolite ritalinic acid, in six healthy subjects who received methylphenidate and ethanol under controlled conditions. Subjects (three males, three females) received a single oral dose of methylphenidate (20 mg; two 10-mg tablets) followed by consumption of ethanol (0.6 g/kg) 30 min later. Methylphenidate, ritalinic acid, and ethylphenidate were quantified using liquid chromatography-tandem mass spectrometry. Ethylphenidate was detectable in the plasma and urine of all subjects after ethanol ingestion. The mean (+/-S.D.) area under the concentration versus time curve for ethylphenidate was 1.2 +/- 0.7 ng/ml/h, representing 2.3 +/- 1.3% that of methylphenidate (48 +/- 12 ng/ml/h). A significant correlation was observed between the area under the concentration versus time curve of methylphenidate and that of ethylphenidate. In view of the known dopaminergic activity of racemic ethylphenidate, it remains possible that under certain circumstances of higher level dosing, e.g., in the abuse of methylphenidate and ethanol, the metabolite ethylphenidate may contribute to drug effects.

Adult↗

A simple model to estimate survival after retransplantation of the liver.

To formulate a model predicting survival after liver retransplantation, we analyzed in detail the last 150 cases of hepatic retransplantation at UCLA. Cox proportional hazards regression analysis identified five variables that demonstrated independent simultaneous prognostic value in estimating patient survival after retransplantation: (1) age group (pediatric or adult), (2) recipient requiring preoperative mechanical ventilation, (3) donor organ cold ischemia > or =12 hr, (4) preoperative serum creatinine, and (5) preoperative serum total bilirubin. The Cox regression equation that predicts survival based on these covariates was simplified by assigning individual patients a risk classification based on a 5-point scoring system. We demonstrate that this system can be employed to identify a subgroup of patients in which the expected outcome is too poor to justify retransplantation. These findings may assist in the rational selection of patients suitable for retransplantation.

Adult↗

Possible dihydroepiandrosterone-induced mania.

BACKGROUND: Dehydroepiandrosterone (DHEA) is among the most abundant steroids in the human body and appears to have diverse biochemical activities. This multifunctional hormone has long been a compound of interest to research psychiatrists. Its recent promotion and availability as an over-the-counter supplement to the general public has led to widespread use. Little is known about potential adverse effects of DHEA when consumed on an acute or chronic basis. We report a case of mania in an older man acutely admitted to our psychiatric facility with no previous personal or family history of bipolar disorder that appeared to be related to recent DHEA use. The patient had initiated DHEA use 6 months prior to admission and was taking 200-300 mg/day at the time of presentation. METHODS: He was treated with valproic acid 500 mg twice daily. RESULTS: The patient showed sufficient improvement to be discharged following a 7-day inpatient hospitalization. CONCLUSIONS: A wide range of medications have been associated with the induction of hypomania and mania, and we have provided a brief discussion of the potential for DHEA to trigger manic symptoms.

Acute Disease↗

Detection of the novel metabolite ethylphenidate after methylphenidate overdose with alcohol coingestion.

Methylphenidate is the most commonly prescribed psychostimulant in clinical use today. Known methylphenidate metabolites include ritalinic acid, corresponding lactams, and p-hydroxymethylphenidate. Recent in vitro work using rat liver preparations has indicated that the methylphenidate ethyl ester, ethylphenidate, is formed upon incubation with ethanol. This report describes the first detection of ethylphenidate in human blood and liver samples obtained from two suicide victims who had overdosed on methylphenidate and coingested ethanol. Amounts of ethylphenidate detected in whole blood specimens in these two cases (8 ng/mL and 1 ng/mL, respectively) were small relative to methylphenidate and ritalinic acid concentrations. Nonetheless, given the high likelihood that methylphenidate and ethanol coingestion frequently occurs, the detection of ethylphenidate in humans warrants further investigation into the extent of its formation as well as into any associated toxicity in nonoverdose situations.

Adult↗

Drug interactions with psychostimulants.

The psychostimulants methylphenidate, dextroamphetamine, and pemoline are among the most common medications used in child and adolescent psychiatry. Often, these agents are used in combination with other medications. This review summarizes reported drug interactions and assesses both causality and clinical significance. A computerized search was undertaken using MEDLINE (1966 to 1998) to obtain all pertinent reports of adverse events associated with the coadministration of psychostimulants and other drugs. A total of 38 reports involving 25 different drugs from various classes were systematically evaluated along with research studies conducted to specifically assess drug interactions. Methylphenidate appeared to be involved primarily in pharmacokinetic interactions suggestive of cytochrome P450 inhibition while dextroamphetamine and pemoline were more often involved in apparent pharmacodynamic interactions. The published data support the safe use of psychostimulants with most classes of medications with few absolute contraindications.

Anticonvulsants↗

Cost of Alzheimer's disease and related dementia in managed-medicare.

BACKGROUND: Managed care organizations (MCOs) will have increased responsibility for the care of large numbers of persons with dementia. There are, however, few studies that inform about decisions of healthcare utilization and expenditures for individuals with dementia in managed care. OBJECTIVES: To examine in a large MCO whether people diagnosed with dementia have higher healthcare utilization and costs than enrollees without dementia. DESIGN: A retrospective study of medical and prescription claims. SETTING: An MCO covering more than 80,000 Medicare enrollees in four geographical locales between January 1, 1996, and March 31, 1998. SUBJECTS: There were 677 paired cases with and without dementia. Controls were selected randomly and matched to cases on age, gender, and region. MEASUREMENTS: Summed total costs and number of claims accrued during the study period, as well as a breakdown of costs and claims with respect to place of service, were annualized and adjusted for age, gender, and comorbid conditions. Costs and claims were broken down by place of service. RESULTS: Dementia prevalence was 0.83%. Mean total costs were 1.5 times higher for patients with dementia relative to controls ($13,487 vs $9,276, P < .001) when annualized and adjusted for level of comorbidity. Almost 75% of the higher costs among cases were linked to inpatient expenses. CONCLUSIONS: Higher costs for individuals with dementia and disproportionate inpatient costs in this MCO parallel patterns among Medicare enrollees in fee-for-service. The high prevalence of dementia among the oldest old coupled with the high costs of dementia care create very significant clinical and financial incentives for managed care plans to improve the care of members suffering from dementia.

Age Distribution↗