61 Heroin Dependence as an Enantiopathy to Quetiapine-Induced Restless Leg Syndrome

Abstract

Introduction: Use of heroin in selfmanagement of Restless Leg Syndrome (RLS) has not heretofore been described. Such a case is presented. METHODS: Case study: This 29 years old right handed male presented with a long history of major depressive disorder, generalized anxiety disorder and opioid dependence. The Patient felt compelled to take quetiapine since was the only drug found to be effective in controlling racing thoughts, Major Depressive Disorder with psychotic features. Prior to use of quetiapine the patient never experienced RLS. Quetiapine in doses ranging from 25 mg to 300 mg a day precipitated severe RLS whereby he was forced to move his leg all night long leading to poor sleep quality. The RLS was unresponsive to Gabapentin and Benztropine, however it was eliminated with a variety of opioids including hydrocodone, buprenorphine, buprenorphine/naloxone. Particularly sensitive to heroin, 1/2 twenty dollar bag, selfadministered IV prior to sleep eliminated the RLS immediately, but when injected more than four hours before sleep it had no effect. RLS acted only when induced with quetiapine, since he wished to continue quetiapine to control his mood, he felt compelled to selfmedicate with heroin to stop RLS side effects. He showed no other signs of extrapyramidal symptomatology or evidence of any other movement disorder. RESULTS: Abnormalities in physical examination: General: Abundance of tattoos on body and face. Cranial Nerve (CN): CN I: Alcohol Sniff Test: 7 cm(anosmia). CN II: Anisocoria OD 5mm OS 2 mm. Motor Examination: drift testing: right pronator drift. Cerebellar: Finger to Nose: end point dysmetria bilaterally. Low amplitude high frequency tremor in both upper extremities on extension. Sensory Examination: decreased graphesthesia in both upper extremities. Reflexes: 3 + knee jerks, absent ankle jerks, positive jaw jerk, bilateral palmomental reflex is present. DISCUSSION: This patient has a long history of quetiapine use due to his major depressive disorder with psychotic features and subsequent self-administration of IV heroin reportedly to reduce the symptoms of quetiapineinduced RLS. Heroin elevates dopamine levels in forebrain by blocking inhibitory GABA interneurons near the ventral tegmental area, leading to activation of mesocorticolimbic dopaminergic neurons (Nakagawa 2008, Steidl 2011). The time frame of opioid administration has a critical impact on its efficacy in improving RLS symptoms. However, the drug's effects only up to 3 to 6 hours (Buchfuhrer 2012). In this case administration of heroin more than 4 hours before sleep would not alleviate the RLS symptoms. Patient chose the time of injection, not for hedonic pleasure of heroin, but rather to prevent RLS symptoms. In those with heroin dependence, the possibility that is a result of selfmedication of underlying movement disorder warrants additional investigation. In those with RLS who are unresponsive to other treatment modalities, a trial of opioids maybe worthwhile.