Iatrogenic Mania With Duloxetine: An Emerging Prescription Error

Abstract

Introduction: Duloxetine is an SNRI (selective serotonin norepinephrine reuptake inhibitor) class of drug widely used as an antidepressant. There is no doubt about its potential role in musculoskeletal pain but its indiscriminate use by physicians has probably started showing its dark side. CASE REPORTS: We present 3 case reports with manic symptoms with Duloxetine for condition other than Major Depression. DISCUSSION: While using Duloxetine, risk benefit ratio should be considered as mania may be a less common adverse effect but its seriousness cannot be undermined. CONCLUSION: A cautious approach is needed by physicians while prescribing Duloxetine. KEYWORDS: Duloxetine, mania, drug induced. INTRODUCTION:Duloxetine is an SNRI (selective serotonin norepinephrine reuptake inhibitor) class of drug widely used as an antidepressant. It has also been widely publicized as a pain killer by parent manufacturing and marketing companies, especially in somatic and neuropathic pains. There is no doubt about its potential role in such conditions other than depression but its indiscriminate use by non-psychiatrists has probably started showing its dark side. A pooled data by Dunner et al. (2005) 5 showed that the estimated risk of Duloxetine related manic switching is 0.1% to 0.2% in patients with major depression.However, he also concluded that diagnostic diligence on the part of the investigators was a methodological limitation of the study, which leads us to interpret that the actual risk of manic switching with Duloxetine still remains unknown. According to Viktrup et al. (2004) 9 , Duloxetine does not induce mania or hypomania in women with stress urinary incontinence and without a history of depression. Carta et al. (2006) 2 found a high frequency of manic symptoms in a sample of female patients with fibromyalgia attending a rheumatology outpatient Unit. According to Duloxetine's summary of product characteristics, mania is a rare side effect. However, we present 3 case reports about patients who had been prescribed Duloxetine by physicians for condition other than Major Depression and presented to psychiatry outpatient with manic symptoms.