Benzodiazepine overdose is a serious condition resulting from administration of high doses of drug belonging to the group benzodiazepines. Consequences of such disorder may be lethal and associated with respiratory or cardiac failure. The frequency of benzodiazepine overdose is increasing, designating the prompt diagnosis to be a crucial factor.
Presentation
Benzodiazepine overdose is a common cause of hospitalization in the United States, associated with about 30% of overdose cases. Such incidences fixedly increase in quantity and are important to consider when dealing with patients who have a history of drug abuse or predisposing factors for a possible overdose. These comprise e.g. psychological disorders, post-traumatic stress syndrome in patients with a military background, depressive or suicidal states.
Benzodiazepines are a class of medication with anxiolytic, analgesic, sedative and hypnotic features marking them a target of drug abuse and subsequent overdose [1]. Illegitimate practices and 'doctor shopping', involving patients visiting multiple doctors, lead to the unreasonable prescription of benzodiazepines and consecutive abuse [2]. Psychiatric patients, on the other hand, are known to use benzodiazepines in an attempt of suicide or intentional self-harm [3].
Often, polydrug users execute the administration of benzodiazepines in combination with alcohol, antidepressants or opioids giving rise to the failure of cardiovascular and respiratory systems [4]. Other complications include neurological, renal impairment, muscular complications like hypotonia, and possible hearing loss.
Acute manifestations in overdosed patients usually involve collapse with seizures, cyanosis due to respiratory failure, loss of consciousness, coma and possible cardiac arrest [5]. On examination of the eyes, the patient might have fixed miosis or pinpoint pupil.
Entire Body System
- Hypothermia
Hypothermia may occur. Serious complications are more likely when newer short-acting agents are involved or when other depressant drugs have been ingested. Diagnosis usually is based on the history of ingestion ... [accessmedicine.mhmedical.com]
3.7 Overdose Overdose with a benzodiazepine can cause drowsiness, dysarthria and nystagmus ; very large overdose may cause hypothermia and rhabdomyolysis. [mhra.gov.uk]
Apnoea indicated airway obstruction Large ingestions can rarely cause hypothermia, bradycardia and hypotension. [lifeinthefastlane.com]
[…] possible dose per kg of each drug Co-ingestants e.g. paracetamol Examination CNS depression Neurologic – confusion, dysarthria, nystagmus, lethargy, ataxia, areflexia, hypotonia, seizure Respiratory – depression Cardiovascular – hypotension Metabolic – hypothermia [rch.org.au]
- Gastric Lavage
The use of flumazenil results in complete awakening with restoration of upper airway protective reflexes, thus enabling gastric lavage to be performed and transfer of the patient from the emergency room to another hospital department. [ncbi.nlm.nih.gov]
Initiate gastric lavage for clinically significant recent ingestions (ie, within 30 minutes). Ensure/monitor airway patency/protective reflexes during the above treatments. [anesth.unboundmedicine.com]
Occasionally, gastric lavage and administration of activated charcoal is indicated, but only if the patient is awake and potentially sensitive to benzodiazepines and if a large dose has been ingested within the last 1 to 2 hours. [link.springer.com]
Lyons, Juan Ochoa and Christopher King, Hypothermia: An Unusual Indication for Gastric Lavage, The Journal of Emergency Medicine, 40, 2, (176), (2011). T. [doi.org]
Often, you need only a period of evaluation in a hospital emergency department: If the drugs were taken within the previous 1-2 hours, the doctor may consider gastric lavage. [webmd.com]
Respiratoric
- Dyspnea
Note: preexisting conditions that compromise respiratory function such as chronic obstructive pulmonary disease, sleep apnea, asthma, or pneumonia clinical indicators of changes in respiratory function, such as respiratory rate, dyspnea, hypoxemia, and [mdedge.com]
Cardiovascular
- Hypotension
Although rare, this may result in hypotension, cardiac dysrhythmias, lactic acidosis, seizures, or coma. [emedicine.medscape.com]
Coma, life-threatening hypotension, bradycardia and clinically significant respiratory depression are rare if only a benzodiazepine has been taken. [mhra.gov.uk]
Aggressive/expectant airway management for frank/anticipated inadequacy of protective airway reflexes Supine/Trendelenburg positioning and aggressive IV fluid therapy for hypotension GI decontamination Activated charcoal 1 g/kg PO or per NG tube is effective [anesth.unboundmedicine.com]
Clinical features : CNS depressio n : lethargy, somnolence, hyporeflexia Respiratory depression Mild hypotension Ataxia Slurred speech Carbamazepine and oxcarbazepine: possibly SIADH Diagnostics Routine urine screening for benzodiazepine metabolites [amboss.com]
Musculoskeletal
- Musculoskeletal Pain
Trends in opioid prescribing and co-prescribing of sedative hypnotics for acute and chronic musculoskeletal pain: 2001-2010. Pharmacoepidemiol Drug Saf. 2015 ;24: 885 – 892. Crossref, Medline, Google Scholar 9. [doi.org]
Neurologic
- Confusion
Extreme drowsiness or trouble staying awake Slurred speech or confusion Agitation Lack of muscle coordination Coma How is a benzodiazepine overdose diagnosed? Your healthcare provider will ask about the medicines you take. [drugs.com]
Other effects can include: confusion dizziness jitteriness/excitability slurred speech loss of coordination impaired judgement difficulty in thinking clearly memory loss mood swings and aggressive behaviour. [mydr.com.au]
In long-term users who have developed dependence, cessation of BZDs can result in a withdrawal syndrome, with manifestations including anxiety, irritability, confusion, seizures, and sleep disorders. [1] Alprazolam withdrawal syndrome may be especially [emedicine.medscape.com]
The signs and symptoms of benzodiazepine overdose are: Somnolence Confusion Diminished reflexes Respiratory depression Apnea Respiratory arrest Cardiac arrest The treatment for benzodiazepine overdose is: Discontinue dental treatment Call for assistance [dentalcare.com]
- Slurred Speech
Other effects can include: confusion dizziness jitteriness/excitability slurred speech loss of coordination impaired judgement difficulty in thinking clearly memory loss mood swings and aggressive behaviour. [mydr.com.au]
Clinical features : CNS depressio n : lethargy, somnolence, hyporeflexia Respiratory depression Mild hypotension Ataxia Slurred speech Carbamazepine and oxcarbazepine: possibly SIADH Diagnostics Routine urine screening for benzodiazepine metabolites [amboss.com]
The most common symptoms of overdose include the central nervous system (CNS); depression and intoxication with impaired balance, and slurred speech. Severe symptoms include coma and respiratory depression. [healthguidance.org]
Signs of an Overdose on Xanax, Valium, or Klonopin Symptoms of overdose on Xanax, Valium, or Klonopin include: Drowsiness or extreme fatigue Confusion, agitation, anxiety, and mood changes Dizziness Slurred speech or acting drunk Amnesia Physical weakness [americanaddictioncenters.org]
- Amnesia
BACKGROUND: A prospective study was conducted to investigate the presence of anterograde amnesia in those who attempted suicide by benzodiazepine overdose and to study the correlation with sedation. [ncbi.nlm.nih.gov]
It provides anxiolysis, sedation, hypnosis, skeletal muscle relaxation, anterograde amnesia, respiratory depression and an anticonvulsant effect but has no analgesic properties. [dentalcare.com]
One hundred and thirty patients responded positively to flumazenil, characterized by improved response to painful stimuli, and decreased amnesia. [mjiri.iums.ac.ir]
Important adverse effects include confusion, impaired motor coordination, amnesia, drowsiness, and respiratory depression. [amboss.com]
Signs of an Overdose on Xanax, Valium, or Klonopin Symptoms of overdose on Xanax, Valium, or Klonopin include: Drowsiness or extreme fatigue Confusion, agitation, anxiety, and mood changes Dizziness Slurred speech or acting drunk Amnesia Physical weakness [americanaddictioncenters.org]
- Ataxia
Ataxia was the most common clinical finding following benzodiazepine ingestion in this series. Flumazenil appeared beneficial for the treatment of severe benzodiazepine toxicity in only two patients. [doi.org]
Disposition Most children can be observed at home unless there is significant ataxia or drowsiness. [lifeinthefastlane.com]
Patients with a mild benzodiazepine overdose display drowsiness, dysarthria and ataxia. In large doses, benzodiazepine can cause coma and respiratory depression, and death. [dlib.si]
Clinical features : CNS depressio n : lethargy, somnolence, hyporeflexia Respiratory depression Mild hypotension Ataxia Slurred speech Carbamazepine and oxcarbazepine: possibly SIADH Diagnostics Routine urine screening for benzodiazepine metabolites [amboss.com]
Lethargy, slurred speech, ataxia, coma, and respiratory arrest may occur. Generally, patients with benzodiazepine-induced coma have hyporeflexia and midposition or small pupils. Hypothermia may occur. [accessmedicine.mhmedical.com]
- Stupor
Drowsiness or extreme fatigue Confusion, agitation, anxiety, and mood changes Dizziness Slurred speech or acting drunk Amnesia Physical weakness or lack of coordination Hypotonia (lack of muscle tone) Blurry vision Difficulty breathing or depressed breathing Stupor [americanaddictioncenters.org]
High doses can cause stupor and respiratory depression, which is managed with intubation and mechanical ventilation. [merckmanuals.com]
Below are the symptoms of benzos overdose: Difficulty in breathing Fingernails and lips appear bluish Mentally disturbed or confused Feeling dizzy Blurred vision or double vision Feeling weak Tremors Lack of coordination of muscle movements Stupor Coma [addictionresource.com]
These were identical with those described by McCarron et al for assessing the severity of barbiturate intoxication. 7 A 7 point scale of conscious state (alert, drowsy, stuporous, coma 1–4) was used. [doi.org]
Workup
Benzodiazepine overdose is managed according to possible complications.
A magnetic resonance imaging (MRI) of the brain is a necessity if the patient appears unconscious, comatose and with a possible risk of acidosis. The MRI will expose herniations, edema and diffuse white matter injury (leukoencephalopathy) relatively excluding the lesions of the gray matter. The white matter injury may also be of connection with the use of chemotherapy agents and exposure to toxins e.g. carbon monoxide. Signs of edema and herniation may evolve and be the cause of death if not handled or monitored appropriately [6] [7].
A computed tomography (CT) examination findings include hypodensity in the affected area of the white brain matter, correlating to the clinical picture found in MRI. Reports suggest that early in the disease, the imaging of the patient's brain can appear normal which leads to discharge from the hospital. After about two weeks, a rapid deterioration of the white matter precedes and involves serious changes in consciousness, behavior, gait, parasympathetic system, etc., advancing to dramatic complications like coma or quadriparesis. Thus the importance of monitoring the affected patient is suggested [8].
Urine sample analysis may expose high levels of benzodiazepines [6].
Lumbar puncture with a collection of the cerebrospinal fluid is useful to exclude other diagnoses e.g. herpes simplex virus infection, Epstein-Barr virus disease or other infections associated with brain tissues that cause similar radiologic findings. The analysis includes cell count, protein, and glucose level determination [9].
Electroencephalography (EEG) is optional and used to discover electrical potential abnormalities if the patient experienced neurologic signs e.g. seizures. The EEG might reveal slowing of background in low frequencies [6].
Other Pathologies
- White Matter Lesions
Classically, in cases of DPHL, these lesions are restricted to the periventricular subcortical white matter, sparing the cerebellum or the brain stem [ 4, 6, 7, 13, 16, 19 ] and doesn't enhance after contrast administration. [bmcneurol.biomedcentral.com]
Treatment
Flumazenil is the first specific benzodiazepine antagonist, used as a specific antidote in known or suspected benzodiazepine overdose treatment. [anesthesiageneral.com]
Finding the perfect treatment is only one phone call away! [drugabuse.com]
Amy has completed the American Psychiatric Nurses Association’s course on Effective Treatments for Opioid Use Disorder and continuing education on Screening, Brief Intervention and Referral to Treatment (SBIRT). [drugrehab.com]
The time available for treatment will vary from 20 minutes to 40 minutes. [dentalcare.com]
Prognosis
Please find relevant information on First Aid for Benzodiazepine Overdose regarding cause, signs & symptoms, administration of first aid treatment, prognosis, preventive measures, and additional resources HERE. [dovemed.com]
Three Part Question [In adults with acute opiate overdose] is [concomitant use of benzodiazepines] associated with a [poorer prognosis in terms of death aspiration, admission to ITU] Clinical Scenario A 27 year old man comes into the emergency department [bestbets.org]
With good supportive care prognosis is excellent. Toxic Mechanism: Simple mechanism, they enhance the inhibitory neurotransmitter GABA by increasing the opening frequency of chlorine. [lifeinthefastlane.com]
Prognosis in nontraumatic coma. Ann Int Med 1981; 94: 293–301 PubMed Google Scholar 72. Plum F, Posner JB, editors. Approach to the unconscious patient. In: The diagnosis of stupor and coma. Philadelphia: FA Davis Co, 1980: 345–64 Google Scholar 73. [link.springer.com]
9.1.1 Ingestion 9.1.2 Inhalation 9.1.3 Skin exposure 9.1.4 Eye contact 9.1.5 Parenteral exposure 9.1.6 Other 9.2 Chronic poisoning 9.2.1 Ingestion 9.2.2 Inhalation 9.2.3 Skin exposure 9.2.4 Eye contact 9.2.5 Parenteral exposure 9.2.6 Other 9.3 Course, prognosis [inchem.org]
Etiology
Acute poisoning with benzodiazepines and other hypnotics: etiologic cause, sex/age distribution and clinical outcome. J of IMAB. 2016 Oct-Dec;22(4):1371-1374. DOI: 10.5272/jimab.2016224.1371. [journal-imab-bg.org]
Etiology 4. Clinical Course IV. Benzodiazepine Withdrawal 1. Signs and Symptoms 2. Treatment V. Benzodiazepine Overdose 1. Clinical Presentation 2. Treatment VI. Case Study: Benzodiazepine Drug-Drug Interaction VII. [ce4less.com]
Gökel, Etiological and demographical characteristics of acute adult poisoning in Adana, Turkey, Human & Experimental Toxicology, 26, 5, (401), (2007). M. Schmidt, Benzodiazepine, Suchtmittel in der AINS, 10.1007/978-3-540-33734-8_5, (79-89), (2007). [doi.org]
Today, there are over 50 different agents available on the worldwide market and the high incidence of benzodiazepine overdose mirrors their widespread use and availability. [1][2][3] Etiology Leo Sternbach was an Austrian scientist working for Hoffmann-La [ncbi.nlm.nih.gov]
Use of flumazenil in the diagnosis and treatment of patients with coma of unknown etiology. Crit Care Med 1993; 21: 538–42 PubMed CrossRef Google Scholar 63. Skeie B, Emhjellen S, Wickstrom E, et al. [link.springer.com]
Epidemiology
International Journal of Epidemiology, 22, 838 – 847. Shader, I. R. & Greenblat, D. J. ( 1993 ) Use of benzodiazepines in anxiety disorders. New England Journal of Medicine, 328, 1398 – 1405. [doi.org]
Epidemiology of acute drug poisoning in a tertiary center from Iasi Country, Romania. Hum Exp Toxicol. 2011 Dec;30(12):1896-903. [ PubMed ] 13. Hutton J, Dent A, Buykx P, Burgess S, Flander L, Dietze P. [journal-imab-bg.org]
“This epidemic is almost entirely preventable, as the most common reason to use benzodiazepines is anxiety—which can be treated effectively and much more safely with talk therapy,” said Sean Hennessy, Pharm.D., Ph.D., professor of epidemiology at Penn [einstein.yu.edu]
Pathophysiology
Unfortunately, this syndrome remains of an unclear pathophysiology and with no successful treatment. [ncbi.nlm.nih.gov]
Pharmacotherapy: A Pathophysiologic Approach, 9th edition. Chapter 53: Anxiety Disorders I; Generalized Anxiety, Panic, and Social Anxiety Disorders. Access Pharmacy [online]. DiPiro et al. Pharmacotherapy: A Pathophysiologic Approach, 9th edition. [rxlist.com]
Pharmacotherapy: A Pathophysiologic Approach. 8th ed. http://accesspharmacy.com/content.aspx?aid=7987346. Accessed June 9, 2012. [accesspharmacy.mhmedical.com]
Prevention
"Though broad efforts are underway to prevent overdose from opioid painkillers, there is another class of prescription drugs that require attention—benzodiazepines," she said. [forbes.com]
Vancouver’s Overdose Prevention Society says there were 16 overdoses in the city over two days last week. [globalnews.ca]
Centers for Disease Control and Prevention. National Vital Statistics System. Multiple Cause of Death 1999-2013. Hyattsville, MD: US Department of Health and Human Services, Centers for Disease Control and Prevention; 2014. [doi.org]
According to another expert, the overdose can be prevented if the problem of anxiety is treated well through talk therapy and not by using benzo. [arizonadetoxhelpline.com]
The potential danger of benzodiazepines is no secret: They were involved in about 30% of prescription drug overdose deaths in 2013, second only to opioids, which were involved in 70% of overdose deaths, according to the Centers for Disease Control and Prevention [birminghammaple.com]
References
- Bachhuber MA, Hennessy S, Cunningham CO, Starrels JL. Increasing Benzodiazepine Prescriptions and Overdose Mortality in the United States, 1996–2013. Am J Public Health. 2016;106(4):686-688.
- Peirce GL, Smith MJ, Abate MA, Halverson J. Doctor and pharmacy shopping for controlled substances. Med Care. 2012;50:494–500.
- Shin HI, Lin MC, Lin CC, et al. Benzodiazepine therapy in psychiatric outpatients is associated with deliberate self-poisoning events at emergency departments—a population-based nested case-control study. Psychopharmacology (Berl). 2013;229:665–71.
- Slavova S, Bunn TL, Talbert J. Drug Overdose Surveillance Using Hospital Discharge Data. Public Health Rep. 2014;129(5):437-445.
- Martins SS, Sampson L, Cerdá M, Galea S. Worldwide Prevalence and Trends in Unintentional Drug Overdose: A Systematic Review of the Literature. Am J Public Health. 2015;105(11):e29-e49.
- Aljarallah S, Al-Hussain F. Acute fatal posthypoxic leukoencephalopathy following benzodiazepine overdose: a case report and review of the literature. BMC Neurol. 2015;15:69.
- Kim JH, Chang KH, Song IC, et al. Delayed encephalopathy of acute carbon monoxide intoxication: diffusivity of cerebral white matter lesions. AJNR Am J Neuroradiol. 2003;24(8):1592–7.
- Chang WL, Chang YK, Hsu SY, Lin GJ, Chen SC. Reversible delayed leukoencephalopathy after heroin intoxication with hypoxia: a case report. Acta Neurologica Taiwanica. 2009;18(3):198–202.
- Wallace IR, Dynan C, Esmonde T. One confused patient, many confused physicians: a case of delayed post-hypoxic leucoencephalopathy. QJM Monthly J Assoc Physicians. 2010;103(3):193–4.