Showing papers by "Paul J. Perry published in 1994"

Tricyclic antidepressant concentrations in plasma: an estimate of their sensitivity and specificity as a predictor of response.

Abstract: An analysis of the literature on tricyclic antidepressant level in blood using receiver operating characteristics curves as the primary statistical tool was performed. For nortriptyline, a significant curvilinear relationship between therapeutic response and nortriptyline was observed that ranged from 58 to 148 ng/ml. The sensitivity and specificity for the nortriptyline therapeutic window were 78 and 61%, respectively. The response rate within the therapeutic range was 66% versus 26% outside the therapeutic range. For desipramine, a significant linear relationship between therapeutic response and desipramine concentration in plasma was observed. The threshold concentration in plasma for therapeutic response was 116 ng/ml. The sensitivity and specificity for the desipramine threshold level in blood were 81 and 59%, respectively. The response rate above the threshold level was 51% versus 15% below the therapeutic threshold concentration. For imipramine, a significant curvilinear relationship between therapeutic response and total imipramine (imipramine+desipramine) concentration in plasma was observed between 175 and 350 ng/ml. The sensitivity and specificity for the total imipramine concentrations in plasma were 52 and 74%, respectively. The response rate within the therapeutic range was 67% versus 39% outside the therapeutic range. For amitriptyline, a significant curvilinear relationship between therapeutic response and total amitriptyline (amitriptyline+nortriptyline) concentration in plasma was observed between 93 and 140 ng/ml. The sensitivity and specificity for the total imipramine concentrations in plasma were 37 and 80%, respectively. The response rate within the therapeutic range was 50% versus 30% outside the therapeutic range.

Plasma clozapine concentrations as a predictor of clinical response: a follow-up study.

Abstract: We investigated the relationship between plasma clozapine concentrations and clinical response in treatment-retractory schizophrenic patients. In a previous study, we found that plasma drug concentrations abore 350 ng/mL maximized clinical response in a group of 29 patients. This study represents a follow-up of these original 29 patients over approximately 2 1/2 years of clozapine treatment. We found that during the initial 6-week trial of clozapine, 38% (N=11) of the patients were considered to be responders. With continued treatment, we found that 58% (14 of 24) were classified as responders. Consistent with our previous study, we observed that plasma concentrations were helpful in predicting response

Venlafaxine: a heterocyclic antidepressant

Abstract: The pharmacology, pharmacokinetics, and clinical efficacy of venlafaxine hydrochloride, a new antidepressant, are described. Venlafaxine inhibits the reuptake of serotonin, norepinephrine, and, to a lesser extent, dopamine. In animal models, it does not significantly inhibit muscarinic, histaminic, or adrenergic receptor activity and does not inhibit monoamine oxidase. Venlafaxine is rapidly absorbed and metabolized in the liver to its active metabolite, O-desmethylvenlafaxine (ODV). Time to peak concentration is one to two hours for the parent compound and four to five hours for ODV. The pharmacokinetics of venlafaxine might be dose-dependent, although pharmacokinetic studies have had conflicting results. The major route of elimination is renal; thus, patients with renal dysfunction may require lower doses. In double-blind, placebo-controlled trials of venlafaxine for maintenance therapy, venlafaxine has shown effective antidepressant activity in severely ill patients with major depression. Antidepressant effectiveness may be apparent within two weeks; this finding needs to be replicated. The dosage is 75-375 mg/day administered in two or three divided doses. The strength of the antidepressant response may be correlated with increasing dosage. Nausea is the most commonly reported adverse drug reaction (ADR). Others include somnolence, dizziness, dry mouth, and sweating. All ADRs have commonly occurred at the beginning of therapy and decreased with time. Overall, venlafaxine is well tolerated. Venlafaxine is as effective as other available antidepressants. It may cause fewer anticholinergic, antihistaminic, and antiadrenergic ADRs and may have a quicker onset of therapeutic action than existing antidepressants.

Sertraline-Phenelzine Drug Interaction: A Serotonin Syndrome Reaction

Abstract: OBJECTIVE:To report a serious drug interaction possibly occurring with the monoamine oxidase inhibitor phenelzine and the selective serotonin reuptake inhibitor sertraline.CASE SUMMARY:A 61-year-old woman with treatment-refractory major depressive disorder was being treated unsuccessfully with lithium, phenelzine, thioridazine, and doxepin. Sertraline 100 mg/d was added to the patient's therapy. Within three hours of ingesting the first dose, the patient experienced a dramatic increase in her temperature, pulse, and respirations along with labile blood pressure, and symptoms of rigidity, diaphoresis, shivering, and decreased sensorium. The patient was transported to the emergency room and treated with diazepam 10 mg iv, followed by midazolam 10 mg iv for control of rigidity. She was also intubated. The patient then experienced precipitous falls in her blood pressure and respiratory rate. Ice packs combined with a cooling blanket and dantrolene 80 mg iv were administered to control fever and rigidity, resp...