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Zolpidem-Associated Parasomnia with Serious Self-Injury: A Shot in the Dark
Psychosomatics 2011:52:88 –91
© 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Case Reports Zolpidem-Associated Parasomnia with Serious Self-Injury: A Shot in the Dark Christopher E. Gibson, B.S., Jason P. Caplan, M.D.
B
enzodiazepine receptor agonists (BzRAs) are a commonly prescribed class of medication used in the treatment of insomnia. These medications have been previously associated with various complex sleep behaviors. We report the case of a man admitted with a self-inflicted gunshot wound to the head potentially resulting from complex sleep behavior associated with the use of a BzRA.
Case Report
Mr. D, was a 49-year-old man with no prior psychiatric history was admitted to St. Joseph’s Hospital and Medical Center (a major tertiary care hospital and level 1 trauma center in Phoenix, AZ) with an apparently self-inflicted gunshot wound to the head. It was determined via physical examination and imaging studies that the injury was due to a .22 caliber bullet that had been fired left-to-right through both orbits resulting in destruction of his right eye and significant damage to the left eye, leaving him totally blind and resulting in multiple intracranial sequelae including a right anterior temporal intraparencyhmal hemorrhage, a cerebellar subdural hematoma, and scattered subarachnoid hemorrhage. After extubation on the 15th hospital day, Psychiatry was consulted in the setting of an apparent suicide attempt. On interview, Mr. D was grossly confused and disoriented. He was diagnosed with a delirium with a presumed multifactorial etiology (including his multiple intracranial injuries and a ventilator-associated pneumonia). History was thus initially obtained from his family. Mr. D’s family denied observing any signs of depression or other indication that he had been considering self-harm. His wife reported that on the night of his injury, he had been watching television with her while drinking scotch, which was his usual routine. Of 88
http://psy.psychiatryonline.org
note, his blood alcohol level on admission was 264 mg/dL, although his wife indicated that he did not seem intoxicated. Approximately 30 minutes after he had gone to bed, she heard the gunshot and found him kneeling next to the bed with the gun next to him on the floor. Mr. D’s family reported feeling quite confused about the circumstances of his admission, noting (aside from his never having given any indication of psychiatric illness or suicidality) his extensive military career, firearms expertise, and collection of high caliber handguns all located in his bedroom and capable of inflicting greater damage than the .22 handgun kept on his nightstand. Furthermore, he had been looking forward to an upcoming visit from his son and newborn grandchild who lived in another state. Mr. D’s wife reported that he had recently been started on zolpidem (Ambien) for insomnia. In the weeks prior to his admission, he had experienced multiple episodes of unusual sleep behaviors including sleepwalking and sleep-eating. He had previously reported to her that he had on several occasions woken up in different rooms in the house after falling asleep in his bed with no recollection of how he arrived there. She had also noted food missing from the kitchen during the night and disturbance of the contents of the refrigerator, often in association with his reports of awakening in rooms other than the bedroom. She did not know if he had taken zolpidem on the night of his admission, and no zolpidem levels had been drawn on admission. Received October 15, 2009; revised December 15, 2009; accepted December 16, 2009. From Creighton University School of Medicine, Omaha, NE (CEG); and St. Joseph’s Hospital and Medical Center, Phoenix, AZ (JPC). Send correspondence and reprint requests to Jason P. Caplan, M.D., St. Joseph’s Hospital and Medical Center, 350 W. Thomas Rd., Phoenix, AZ 85013. e-mail: [email protected] © 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Psychosomatics 52:1, January-February 2011
Gibson and Caplan Mr. D’s mental status improved gradually over the remaining course of his hospitalization (totaling 25 days). He steadfastly denied shooting himself, noting the last thing he remembered was going to bed that night. He was unable to specifically recall whether he had taken zolpidem that evening. While he vehemently denied any suicidal ideation, he specifically stated that if he had wished to shoot himself, he would certainly have used a larger caliber weapon. In the context of his prior recent sleep behaviors since starting zolpidem and the absence of any indication of deliberate suicidality, it was theorized that his gunshot wound could be due to a parasomnia. Evidence against a deliberate suicide attempt included the anterior placement of his wound (shooting through the orbits) and the use of the lowest caliber handgun available. Moreover, it was noted that the patient was righthanded, thus it seemed unlikely that he would have deliberately shot himself through the left orbit since, to use his dominant hand, he would have had to flex at both the right wrist and right elbow while rotating his head to the right. Even if he had performed this contortion, it would have been impossible for the bullet to travel through both orbits since it would have been directed posteriorly. Further collateral data indicated that the patient slept on the left side of the bed, with his nightstand (and gun) immediately to his left, which may have facilitated his reaching for the gun and accidentally shooting himself while still asleep. Mr. D was again seen in the hospital 6 months after his initial injury. No additional information had come to light in the intervening period indicating that Mr. D had attempted suicide, and he continued to deny any deliberate self-harm.
Discussion
Zolpidem (Ambien), zaleplon (Sonata) and eszopiclone (Lunesta) are the three benzodiazepine receptor agonists (BzRAs) approved by the FDA for the treatment of insomnia. These medications act selectively on the ␣1GABAA receptors of the central nervous system. Zolpidem acts specifically on the Lamina IV of the sensorimotor cortical regions, substantia nigra, cerebellar molecular layer, olfactory bulb, ventral thalamic complex, pons, inferior colliculus, and globus pallidus. BzRAs bind allosterically to the GABA receptor enhancing the effect of the neurotransmitter at the ␣1-GABAA Psychosomatics 52:1, January-February 2011
receptor, thus creating a GABA-ergic effect. Chloride ion channels are opened upon the binding of GABA, leading to neuronal hyperpolarization and decreased action potential generation. This results in sedative, amnestic, and motor-impairing effects within the central nervous system. The mechanism of action of BzRAs differs from benzodiazepines in that the latter bind to each of the ␣1-, ␣2-, ␣3-, and ␣5-GABAA receptor subtypes producing the aforementioned results as well as anxiolytic and alcohol-potentiating effects, muscle relaxation, anterograde amnesia, and motor incoordination. The relative selectivity of BzRAs for the ␣1GABAA subtype most likely explains why they lack these specific side effects.1 Parasomnias have been defined as the group of primary sleep disorders that feature abnormal behaviors or physiologic phenomena occurring during sleep or the transition from wakefulness to sleep. This group of sleep disorders can be subdivided into nonrapid eye movement (NREM) sleep disorders (e.g., sleepwalking, sleep terrors) and rapid eye movement (REM) sleep disorders (nightmare disorder, REM behavior disorder). A third group of diffuse sleep disorders features parasomnias that can occur during any phase of sleep (e.g., sleep-related seizures).2 Previous reports have associated BzRAs with various parasomnias including such complex behaviors as sleep-eating, somnambulism, hallucinations, sleep-walking with object manipulation, sleep conversation, sleep driving, sleep sex, and sleep shopping. There have been several articles examining both sleep-eating and somnambulism. One recent literature review by Dolder and Nelson found eight cases of nocturnal sleep-related eating disorder (NSRED) out of 17 patients with BzRA-induced complex behaviors, seven of which involved zolpidem.1 Four of these patients were also concurrently using antidepressants, which were suspected to increase the serum concentration of zolpidem. The authors concluded that either initiation or dose escalation of zolpidem can induce complex behaviors such as NSRED.1 Furthermore, a 2008 case report demonstrated an association between the switch from immediate-release zolpidem to the extended release form with the onset of complex sleep behaviors.3 The report further suggests that in some individuals the absorption of zolpidem ER may result in higher peak blood levels, leading to complex sleep behaviors. Previous reports have described sleep behaviors with object manipulation as complicated (and potentially dangerous) as attempting to operate a lawn mower or drive a car, however, we http://psy.psychiatryonline.org
89
Case Reports believe that this is the first report of a parasomnia involving the manipulation of a firearm with resultant self-injury.4,5 There has also been some suggestion that certain conditions may indicate a predisposition to NSRED. These disorders include nocturnal eating, restless leg syndrome, periodic limb movement disorder, and sleep apnea.1,6 Another case series examining zolpidem-induced somnambulism and sleep-eating suggests an association between these complex behaviors and factors such as obesity, hunger, chronic dieting, alcoholism, drug abuse, stress, anxiety, and sexual abuse in women during childhood.7 The package insert for Ambien specifically notes that the combination of the drug with alcohol (as seen in this case) or other CNS depressants increases the risk of parasomnias.8 One 2008 study examining patients on zolpidem demonstrated that patients experiencing somnambulism were actually on a lower dose of the drug than those who reported no side effects, although the difference was not statistically significant and this study was limited by its retrospective design.9 A 2005 case report demonstrated a connection between zolpidem use and somnambulism in a male rehabilitation patient with a history of alcoholism and traumatic brain injury, with resolution of his complex sleep behaviors upon discontinuation of zolpidem.10 It has been theorized that of the BzRAs, zolpidem carries a higher risk of complex sleep behaviors due to its greater ␣1-GABAA binding affinity. Moreover, the metabolism of zolpidem via the cytochrome P450 3A4 isoenzyme can be inhibited by drugs that interfere with this pathway, increasing the serum concentration of the medication. Commonly prescribed 3A4 inhibitors include antibiotics (clarithromycin, erythromycin, ciprofloxacin), HIV antivirals (indinavir, ritonavir, nelfinavir), antidepressants (fluoxetine, fluvoxamine, nefazodone), calcium channel blockers (verapamil, diltiazem), and antifungal agents (ketoconazole, fluconazole, itraconazole).11 It has also been suggested that the more frequent reporting of zolpidem-induced complex behaviors is
due to its ubiquitous usage.1 In 2006 alone (the last year Ambien remained on patent), US sales totaled $2.2 billion. Given the high frequency of use, even relatively rare adverse effects are likely to occur in a significant number of patients and potentially result in confusing presentations that may come to the attention of psychiatrists practicing in the general hospital.12 An additional adverse effect of BzRAs that may result in complex psychiatric presentations is the occurrence of compulsive behaviors with anterograde amnesia. Thus, the differential diagnosis of patients who engage in bizarre or self-harming behaviors, which they later do not recall while using BzRAs includes both complex sleep behaviors and intoxication with anterograde amnesia.13 Despite the uncertainty surrounding the role of BzRAs in complex sleep behaviors, these drugs should likely be stopped if complex sleep behaviors present de novo during their use. Alternative interventions for the treatment of insomnia including antihistamines, sedating antidepressants, and cognitive behavioral therapy can be substituted for BzRAs in these circumstances. Care should be taken in the identification of risk factors and prior episodes of complex sleep behaviors. Close attention should also be paid to the concurrent use of 3A4 inhibiting agents, since they may dramatically increase the serum concentration of the BzRA. While parasomnias remain a relatively rare adverse effect of the BzRA agents, the potential danger they may pose (as demonstrated by this case) renders them a significant risk of BzRA use. Patients being prescribed these medications, particularly those with prior history of parasomnias, should be cautioned as to the possibility of their occurrence. The specific contraindication of combining alcohol and BzRAs should be reinforced to patients. Furthermore, the authors recommend that the accessibility of firearms in the bedroom while these medications are being used should be a subject of discussion between prescriber and patient in order to forestall potentially life-threatening consequences.
References 1. Dolder CR, Nelson MH: Hyposedative-induced complex behaviours: incidence, mechanisms and management. CNS Drugs 2008; 22:1021–1036 2. Smallwood P, Stern TA: Patients with disordered sleep, in Massachusetts General Hospital Handbook of General Hospital Psychiatry, 5th edition. Edited by Stern TA, Fricchione GL, Cassem NH, et al. Philadelphia, PA, Mosby, 2004, pp 531–546 3. Chiang A, Krystal A: Report of two cases where sleep related eating behavior occurred with the extended-release formulation but not the immediate-release formulation of a sedativehypnotic agent. J Clin Sleep Med 2008; 4:155–156
90
http://psy.psychiatryonline.org
4. Liskow B, Pikalov A: Zaleplon overdose associated with sleepwalking and complex behavior. J Am Acad Child Adolesc Psychiatry 2004; 43:927–928 5. Doane JA, Dalpiaz AS: Zolpidem-induced sleep-driving. Am J Med 2008; 121:e5 6. Morgenthaler TI, Silber MH: Amnestic sleep-related eating disorder associated with zolpidem. Sleep Med 2002; 3:323– 327 7. Dang A, Garg G, Rataboli PV: Zolpidem induced nocturnal sleep-related eating disorder (NSRED) in a male patient. Int J Eat Disord 2009; 42:385–386
Psychosomatics 52:1, January-February 2011
Gibson and Caplan 8. Ambien [package insert]. Bridgewater, NJ: Sanofi-Aventis U.S. LLC; 2008 9. Tsai JH, Yang P, Chen CC, et al: Zolpidem-induced amnesia and somnambulism: rare occurrences? Eur Neuropsychopharmacol 2009; 19:74 –76 10. Yang W, Dollear M, Muthukrishnan SR: One rare side effect of zolpidem—sleepwalking: a case report. Arch Phys Med Rehabil 2005; 86:1265–1266
Psychosomatics 52:1, January-February 2011
11. Flockhart DA: Drug Interactions: Cytochrome P450 Drug Interaction Table. Indiana University School of Medicine (2007). Available at: http://medicine.iupui.edu/clinpharm/ddis/table.asp. Accessed December 2, 2009 12. Available at: http://pharmacytimes.com/issue/pharmacy/2007/ 2007-05/2007-05-6505. Accessed December 14, 2009 13. Tsai MJ, Tsai YH, Huang YB: Compulsive behavior and anterograde amnesia after zolpidem use. Clin Toxicol (Phila) 2007; 45:179–181
http://psy.psychiatryonline.org
91
© 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Case Reports Zolpidem-Associated Parasomnia with Serious Self-Injury: A Shot in the Dark Christopher E. Gibson, B.S., Jason P. Caplan, M.D.
B
enzodiazepine receptor agonists (BzRAs) are a commonly prescribed class of medication used in the treatment of insomnia. These medications have been previously associated with various complex sleep behaviors. We report the case of a man admitted with a self-inflicted gunshot wound to the head potentially resulting from complex sleep behavior associated with the use of a BzRA.
Case Report
Mr. D, was a 49-year-old man with no prior psychiatric history was admitted to St. Joseph’s Hospital and Medical Center (a major tertiary care hospital and level 1 trauma center in Phoenix, AZ) with an apparently self-inflicted gunshot wound to the head. It was determined via physical examination and imaging studies that the injury was due to a .22 caliber bullet that had been fired left-to-right through both orbits resulting in destruction of his right eye and significant damage to the left eye, leaving him totally blind and resulting in multiple intracranial sequelae including a right anterior temporal intraparencyhmal hemorrhage, a cerebellar subdural hematoma, and scattered subarachnoid hemorrhage. After extubation on the 15th hospital day, Psychiatry was consulted in the setting of an apparent suicide attempt. On interview, Mr. D was grossly confused and disoriented. He was diagnosed with a delirium with a presumed multifactorial etiology (including his multiple intracranial injuries and a ventilator-associated pneumonia). History was thus initially obtained from his family. Mr. D’s family denied observing any signs of depression or other indication that he had been considering self-harm. His wife reported that on the night of his injury, he had been watching television with her while drinking scotch, which was his usual routine. Of 88
http://psy.psychiatryonline.org
note, his blood alcohol level on admission was 264 mg/dL, although his wife indicated that he did not seem intoxicated. Approximately 30 minutes after he had gone to bed, she heard the gunshot and found him kneeling next to the bed with the gun next to him on the floor. Mr. D’s family reported feeling quite confused about the circumstances of his admission, noting (aside from his never having given any indication of psychiatric illness or suicidality) his extensive military career, firearms expertise, and collection of high caliber handguns all located in his bedroom and capable of inflicting greater damage than the .22 handgun kept on his nightstand. Furthermore, he had been looking forward to an upcoming visit from his son and newborn grandchild who lived in another state. Mr. D’s wife reported that he had recently been started on zolpidem (Ambien) for insomnia. In the weeks prior to his admission, he had experienced multiple episodes of unusual sleep behaviors including sleepwalking and sleep-eating. He had previously reported to her that he had on several occasions woken up in different rooms in the house after falling asleep in his bed with no recollection of how he arrived there. She had also noted food missing from the kitchen during the night and disturbance of the contents of the refrigerator, often in association with his reports of awakening in rooms other than the bedroom. She did not know if he had taken zolpidem on the night of his admission, and no zolpidem levels had been drawn on admission. Received October 15, 2009; revised December 15, 2009; accepted December 16, 2009. From Creighton University School of Medicine, Omaha, NE (CEG); and St. Joseph’s Hospital and Medical Center, Phoenix, AZ (JPC). Send correspondence and reprint requests to Jason P. Caplan, M.D., St. Joseph’s Hospital and Medical Center, 350 W. Thomas Rd., Phoenix, AZ 85013. e-mail: [email protected] © 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
Psychosomatics 52:1, January-February 2011
Gibson and Caplan Mr. D’s mental status improved gradually over the remaining course of his hospitalization (totaling 25 days). He steadfastly denied shooting himself, noting the last thing he remembered was going to bed that night. He was unable to specifically recall whether he had taken zolpidem that evening. While he vehemently denied any suicidal ideation, he specifically stated that if he had wished to shoot himself, he would certainly have used a larger caliber weapon. In the context of his prior recent sleep behaviors since starting zolpidem and the absence of any indication of deliberate suicidality, it was theorized that his gunshot wound could be due to a parasomnia. Evidence against a deliberate suicide attempt included the anterior placement of his wound (shooting through the orbits) and the use of the lowest caliber handgun available. Moreover, it was noted that the patient was righthanded, thus it seemed unlikely that he would have deliberately shot himself through the left orbit since, to use his dominant hand, he would have had to flex at both the right wrist and right elbow while rotating his head to the right. Even if he had performed this contortion, it would have been impossible for the bullet to travel through both orbits since it would have been directed posteriorly. Further collateral data indicated that the patient slept on the left side of the bed, with his nightstand (and gun) immediately to his left, which may have facilitated his reaching for the gun and accidentally shooting himself while still asleep. Mr. D was again seen in the hospital 6 months after his initial injury. No additional information had come to light in the intervening period indicating that Mr. D had attempted suicide, and he continued to deny any deliberate self-harm.
Discussion
Zolpidem (Ambien), zaleplon (Sonata) and eszopiclone (Lunesta) are the three benzodiazepine receptor agonists (BzRAs) approved by the FDA for the treatment of insomnia. These medications act selectively on the ␣1GABAA receptors of the central nervous system. Zolpidem acts specifically on the Lamina IV of the sensorimotor cortical regions, substantia nigra, cerebellar molecular layer, olfactory bulb, ventral thalamic complex, pons, inferior colliculus, and globus pallidus. BzRAs bind allosterically to the GABA receptor enhancing the effect of the neurotransmitter at the ␣1-GABAA Psychosomatics 52:1, January-February 2011
receptor, thus creating a GABA-ergic effect. Chloride ion channels are opened upon the binding of GABA, leading to neuronal hyperpolarization and decreased action potential generation. This results in sedative, amnestic, and motor-impairing effects within the central nervous system. The mechanism of action of BzRAs differs from benzodiazepines in that the latter bind to each of the ␣1-, ␣2-, ␣3-, and ␣5-GABAA receptor subtypes producing the aforementioned results as well as anxiolytic and alcohol-potentiating effects, muscle relaxation, anterograde amnesia, and motor incoordination. The relative selectivity of BzRAs for the ␣1GABAA subtype most likely explains why they lack these specific side effects.1 Parasomnias have been defined as the group of primary sleep disorders that feature abnormal behaviors or physiologic phenomena occurring during sleep or the transition from wakefulness to sleep. This group of sleep disorders can be subdivided into nonrapid eye movement (NREM) sleep disorders (e.g., sleepwalking, sleep terrors) and rapid eye movement (REM) sleep disorders (nightmare disorder, REM behavior disorder). A third group of diffuse sleep disorders features parasomnias that can occur during any phase of sleep (e.g., sleep-related seizures).2 Previous reports have associated BzRAs with various parasomnias including such complex behaviors as sleep-eating, somnambulism, hallucinations, sleep-walking with object manipulation, sleep conversation, sleep driving, sleep sex, and sleep shopping. There have been several articles examining both sleep-eating and somnambulism. One recent literature review by Dolder and Nelson found eight cases of nocturnal sleep-related eating disorder (NSRED) out of 17 patients with BzRA-induced complex behaviors, seven of which involved zolpidem.1 Four of these patients were also concurrently using antidepressants, which were suspected to increase the serum concentration of zolpidem. The authors concluded that either initiation or dose escalation of zolpidem can induce complex behaviors such as NSRED.1 Furthermore, a 2008 case report demonstrated an association between the switch from immediate-release zolpidem to the extended release form with the onset of complex sleep behaviors.3 The report further suggests that in some individuals the absorption of zolpidem ER may result in higher peak blood levels, leading to complex sleep behaviors. Previous reports have described sleep behaviors with object manipulation as complicated (and potentially dangerous) as attempting to operate a lawn mower or drive a car, however, we http://psy.psychiatryonline.org
89
Case Reports believe that this is the first report of a parasomnia involving the manipulation of a firearm with resultant self-injury.4,5 There has also been some suggestion that certain conditions may indicate a predisposition to NSRED. These disorders include nocturnal eating, restless leg syndrome, periodic limb movement disorder, and sleep apnea.1,6 Another case series examining zolpidem-induced somnambulism and sleep-eating suggests an association between these complex behaviors and factors such as obesity, hunger, chronic dieting, alcoholism, drug abuse, stress, anxiety, and sexual abuse in women during childhood.7 The package insert for Ambien specifically notes that the combination of the drug with alcohol (as seen in this case) or other CNS depressants increases the risk of parasomnias.8 One 2008 study examining patients on zolpidem demonstrated that patients experiencing somnambulism were actually on a lower dose of the drug than those who reported no side effects, although the difference was not statistically significant and this study was limited by its retrospective design.9 A 2005 case report demonstrated a connection between zolpidem use and somnambulism in a male rehabilitation patient with a history of alcoholism and traumatic brain injury, with resolution of his complex sleep behaviors upon discontinuation of zolpidem.10 It has been theorized that of the BzRAs, zolpidem carries a higher risk of complex sleep behaviors due to its greater ␣1-GABAA binding affinity. Moreover, the metabolism of zolpidem via the cytochrome P450 3A4 isoenzyme can be inhibited by drugs that interfere with this pathway, increasing the serum concentration of the medication. Commonly prescribed 3A4 inhibitors include antibiotics (clarithromycin, erythromycin, ciprofloxacin), HIV antivirals (indinavir, ritonavir, nelfinavir), antidepressants (fluoxetine, fluvoxamine, nefazodone), calcium channel blockers (verapamil, diltiazem), and antifungal agents (ketoconazole, fluconazole, itraconazole).11 It has also been suggested that the more frequent reporting of zolpidem-induced complex behaviors is
due to its ubiquitous usage.1 In 2006 alone (the last year Ambien remained on patent), US sales totaled $2.2 billion. Given the high frequency of use, even relatively rare adverse effects are likely to occur in a significant number of patients and potentially result in confusing presentations that may come to the attention of psychiatrists practicing in the general hospital.12 An additional adverse effect of BzRAs that may result in complex psychiatric presentations is the occurrence of compulsive behaviors with anterograde amnesia. Thus, the differential diagnosis of patients who engage in bizarre or self-harming behaviors, which they later do not recall while using BzRAs includes both complex sleep behaviors and intoxication with anterograde amnesia.13 Despite the uncertainty surrounding the role of BzRAs in complex sleep behaviors, these drugs should likely be stopped if complex sleep behaviors present de novo during their use. Alternative interventions for the treatment of insomnia including antihistamines, sedating antidepressants, and cognitive behavioral therapy can be substituted for BzRAs in these circumstances. Care should be taken in the identification of risk factors and prior episodes of complex sleep behaviors. Close attention should also be paid to the concurrent use of 3A4 inhibiting agents, since they may dramatically increase the serum concentration of the BzRA. While parasomnias remain a relatively rare adverse effect of the BzRA agents, the potential danger they may pose (as demonstrated by this case) renders them a significant risk of BzRA use. Patients being prescribed these medications, particularly those with prior history of parasomnias, should be cautioned as to the possibility of their occurrence. The specific contraindication of combining alcohol and BzRAs should be reinforced to patients. Furthermore, the authors recommend that the accessibility of firearms in the bedroom while these medications are being used should be a subject of discussion between prescriber and patient in order to forestall potentially life-threatening consequences.
References 1. Dolder CR, Nelson MH: Hyposedative-induced complex behaviours: incidence, mechanisms and management. CNS Drugs 2008; 22:1021–1036 2. Smallwood P, Stern TA: Patients with disordered sleep, in Massachusetts General Hospital Handbook of General Hospital Psychiatry, 5th edition. Edited by Stern TA, Fricchione GL, Cassem NH, et al. Philadelphia, PA, Mosby, 2004, pp 531–546 3. Chiang A, Krystal A: Report of two cases where sleep related eating behavior occurred with the extended-release formulation but not the immediate-release formulation of a sedativehypnotic agent. J Clin Sleep Med 2008; 4:155–156
90
http://psy.psychiatryonline.org
4. Liskow B, Pikalov A: Zaleplon overdose associated with sleepwalking and complex behavior. J Am Acad Child Adolesc Psychiatry 2004; 43:927–928 5. Doane JA, Dalpiaz AS: Zolpidem-induced sleep-driving. Am J Med 2008; 121:e5 6. Morgenthaler TI, Silber MH: Amnestic sleep-related eating disorder associated with zolpidem. Sleep Med 2002; 3:323– 327 7. Dang A, Garg G, Rataboli PV: Zolpidem induced nocturnal sleep-related eating disorder (NSRED) in a male patient. Int J Eat Disord 2009; 42:385–386
Psychosomatics 52:1, January-February 2011
Gibson and Caplan 8. Ambien [package insert]. Bridgewater, NJ: Sanofi-Aventis U.S. LLC; 2008 9. Tsai JH, Yang P, Chen CC, et al: Zolpidem-induced amnesia and somnambulism: rare occurrences? Eur Neuropsychopharmacol 2009; 19:74 –76 10. Yang W, Dollear M, Muthukrishnan SR: One rare side effect of zolpidem—sleepwalking: a case report. Arch Phys Med Rehabil 2005; 86:1265–1266
Psychosomatics 52:1, January-February 2011
11. Flockhart DA: Drug Interactions: Cytochrome P450 Drug Interaction Table. Indiana University School of Medicine (2007). Available at: http://medicine.iupui.edu/clinpharm/ddis/table.asp. Accessed December 2, 2009 12. Available at: http://pharmacytimes.com/issue/pharmacy/2007/ 2007-05/2007-05-6505. Accessed December 14, 2009 13. Tsai MJ, Tsai YH, Huang YB: Compulsive behavior and anterograde amnesia after zolpidem use. Clin Toxicol (Phila) 2007; 45:179–181
http://psy.psychiatryonline.org
91