ABSTRACT
The antidepressant mirtazapine antagonizes central presynaptic alpha2-adrenergic auto- and heteroreceptors resulting in increased central norepinephrine and serotonin activity. Histamine H2 receptors are also antagonized, as are postsynaptic serotonin 5-HT2 and 5-HT3 receptors, leading to serotonergic activity primarily via 5-HT1A receptors. Based on the case report of a patient who developed mania with higher than recommended dosage of mirtazapine, we review the literature on the atypical nature of manic symptoms with mirtazapine. Eight subjects, including those in our study, were identified as having developed mirtazapine-induced mania with atypical features, consisting of dysphoria, irritability, insomnia, psychomotor agitation and abnormal gait. Predisposing features may have included the presence of underlying brain dysfunction and certain selective serotonin reuptake inhibitor-mirtazapine combinations. Dysphoric mania with atypical features may be induced by mirtazapine, providing support for a common hypothesis such as 'central norepinephrine hyperactivity' as the basis for development of mania with mirtazapine.
Subject(s)
Antidepressive Agents, Second-Generation/adverse effects , Bipolar Disorder/chemically induced , Mianserin/adverse effects , Norepinephrine/pharmacology , Adult , Antidepressive Agents, Second-Generation/administration & dosage , Antidepressive Agents, Second-Generation/therapeutic use , Depressive Disorder/drug therapy , Dose-Response Relationship, Drug , Female , Humans , Mianserin/administration & dosage , Mianserin/analogs & derivatives , Mianserin/therapeutic use , Mirtazapine , Risk Factors , Selective Serotonin Reuptake Inhibitors/therapeutic use , SyndromeABSTRACT
A convenient high-performance liquid chromatographic (HPLC) assay was developed for determination of sotalol (STL) enantiomers in plasma. Following addition of the internal standard (IS; racemic atenolol), enantiomers of STL and IS were extracted using ethyl acetate. After evaporation of the organic layer, samples were derivatized with a solution of S-(+)-1-(1-naphthyl)ethyl isocyanate (NEIC). The resulting diastereomers were chromatographed with normal-phase HPLC with chloroform:hexane:methanol [65:33:2 (v/v)] as the mobile phase at a flow rate of 2 ml/min. The fluorescence detection wavelength was set at 220 nm for excitation with no emission filter. The suitability of the assay for pharmacokinetic studies was determined by measuring STL enantiomers in the plasma of a healthy subject after administration of a single 160-mg oral, racemic dose of STL.