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Unconsciousness

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Synonyms and keywords: LOC: non responsive; unresponsive; non-responsive; non-responsiveness; unresponsiveness; lack of responsiveness; lack of response; reduced alertness; disturbance of consciousness; decreased level of consciousness; decreased LOC; decreased consciousness; partial loss of consciousness; loss of consciousness; lack of consciousness

Overview

Overview

Unconsciousness is a dramatic alteration of mental state that involves complete or near-complete lack of responsiveness to people and other environmental stimuli. A transient LOC followed by rapid recovery is referred to as syncope.

Causes

Causes

Common Causes

Causes by Organ System

Cardiovascular Cardiac arrest, Pulmonary arteriovenous fistula, Shock, Syncope, Ventricular fibrillation, Fat embolism
Chemical / poisoning 1,1-Dichloroethene, 1,4-Dioxane, 2,4-Dinitrotoluene, 2-Methyl-4-Chlorophenoxyacetic Acid, Acetone, Acetophenone, Acute varnish makers’ and painters’ Naptha, Allyl alcohol, Allyl chloride, Allyl trichloride, Aluminum phosphide, Amidithion, Amiton, Aniline, Antifreeze, Athyl-Gusathion, Azinophos-methyl, Azinfos-ethyl, Azinphosmetile, Azothoate, Benoxafos, Bromophos, Cadusafos, Cannabinoids, Carbon monoxide, Carbon tetrachloride, Carbophenothion, Chlorfenvinphos, Chlorobenzene, Chloropyrifos, Chlorpyrifos methyl, Claviceps purpurea, Cone shell , Cyanides, Cyanthoate, Cyclohexanone, Demeton, Demeton-methyl, Demeton-O, Demeton-O-methyl, Demeton-S-methyl, Demeton-S-methylsulphon, Dialifos, Diazinon, Dichlorvos, Dicrotophos, Diethylene glycol, Dimethoate, Dimethyl phthalate, Dioxathion, Disulfoton, Earthball, Endosulfan, Endothion, Ethinamate, Ethion, Ethoate-methyl, Ethoprophos, Ethyl mercaptan, Ethylbenzene, Ethyl-guthion, Etrimfos, Fenchlorphos, Fenitrothion, Fensulfothion, Fenthion, Fonophos, Formothion, Guthion-ethyl, Heptenophos, High melting explosive , Insect allergy, Iodofenphos, Jet Fuel-4, Jet Fuel-8, Malathion, Mecarbam, Methacrifos, Methamidophos, Methane, Methidathion, Methiocarb, Methomyl, Methyl ethyl ketone, Methyl mercaptan, Methyl parathion, Methyl tert-butyl ether, Methylene Chloride, Metiltriazotion, Mevinphos, Monocrotophos, N,N-Dimethyl-P-Toluidine, Naphthalene, Nitroethane, Nitromethane, Nitrophenol, Nitrophenol Urea, Omethoate, Oxydeprofos, Oxydisulfoton, Parathion, Parathion Methyl, Pentaborane, Pentachlorophenol, Phenkapton, Phorate, Phosalone, Phosdrin, Phosmet, Phosphamidon, Phosphine, Phoxim, Pine oil, Pirimiphos-methyl, Primiphos methyl, Profenofos, Propylene glycol dinitrate, Prothidathion, Prothoate, Pyridine, Pyrimitate, Quinalphos, Quintiofos, RDX, Selenium, Sodium azide, Sodium hypochlorite, Sophamide, Stoddard solvent, Sulfotep, Terbufos, Tetrachloroethylene, Tetraethyl Pyrophosphate, Tetrahydrocannabinol, Tetrahydrofuran, Thiometon, Tolclofos methyl, Toluene, Triazophos, Triazotion, Trichlorfon, Trichloroethane, Triclofos, Trifenfos, Vamidothion, Vinyl Choride, Water hemlock poisoning, Xylene, Zinc Phosphide, Iron compounds, Organophosphorous compounds
Dermatologic No underlying causes
Drug Side Effect Atropine, Baclofen, Buprenorphine, Buspirone, Chlophedianol, Chloral hydrate, Chlorpheniramine, Chlorpromazine, Cinnarizine, Clomipramine, Clonazepam, Clotiapine, Cocaine, Codeine, Cyclobenzaprine, Cycloserine, Dantrolene, Demerol , Demethyldiazepam, Deserpidine, Desipramine, Diamorphine, Diazepam, Dichloralphenazone, Diphenhydramine, Diphenidol, Dothiepin, Doxepin , Efavirenz, Eszopiclone, Ethchlorvynol, ferumoxytol, Flurazepam , Fluridrazepam, Gabapentin, Gamma hydroxybutyrate, Ganaxolone, General anaesthesia, Glutethimide, Haloperidol, Hydrazine, Hydroxyzine, Imipramine, Inhalational anaesthetics, Iron compounds, Levetiracetam, Levomepromazine, Lidocaine, Local anaesthetia, Lofexidine, Lorazepam, Medazepam, Melatonin, Mephenoxalone, Meprobamate, Methadone, Methaqualone, Methyldopa, Methyprylon, Metoclopramide, Mianserin, Midazolam, Mirtazapine, Morphine, Nabilone, Nitrazepam, Nitrous oxide, Nortriptyline, Novacaine, Olanzapine, Oprelvekin, Oxazepam, Penicillin, Perazine, Phencyclidine, Phenelzine, Phenobarbital, Pipothiazine, Pizotifen, Pramipexole, Prazepam, Pregabalin, Primidone, Prochlorperazine, Propiomazine, Propofol, Protriptyline, Quetiapine, Ramelteon, Reserpine, Ritalin, Sulfa antibiotics, Temazepam, Thiopentone, Tizanidine, Topiramate, Tricyclic antidepressants, Trifluperidol, Trimipramine, Ultram , Vigabatrin, Zaleplon, Ziconotide, Zolpidem, Zopiclone, Amitriptyline, Amoxapine, Antipsychotic agents, Barbiturates, Benzodiazepines, Bromazepam
Ear Nose Throat No underlying causes
Endocrine Diabetic ketoacidosis, Hyperosmolar non-ketotic diabetic coma, Hypothyroidism
Environmental Heat stroke
Gastroenterologic Hepatic failure, Variceal Bleeding
Genetic Hereditary fructose-1-phosphate aldolase deficiency, Fumarase deficiency, Long chain hydroxyacyl-CoA dehydrogenase deficiency, Mitochondrial acetoacetyl-CoA thiolase deficiency, Unverricht-Lundborg disease, Progressive myoclonus epilepsy, Carbamoylphosphate synthetase 1 deficiency , Carnitine deficiency , Carnitine-acylcarnitine translocase deficiency
Hematologic Anemia, Thrombotic thrombocytopenic purpura
Iatrogenic Ureterosigmoidostomy
Infectious Disease Malaria, Viral meningitis, Rabies, Sleeping sickness , Intracranial abscess, Meningoencephalitis
Musculoskeletal / Ortho No underlying causes
Neurologic Acute hemorrhagic leukoencephalitis, Alcohol withdrawal syndrome, Anencephaly, Brain death, Cataplexy, Epidural haemorrhage, Fits, Focal seizures, Intracranial abscess, Intracranial granuloma, Intracranial haemorrhage, Meningoencephalitis, Partial seizure, Pituitary apoplexy, Progressive myoclonus epilepsy, Raised intracranial pressure, Secondarily generalized seizure, Subarachnoid haemorrhage, Subdural haemorrhage, Syncope, Unverricht-Lundborg disease
Nutritional / Metabolic Arginosuccinic aciduria, Carbamoylphosphate synthetase 1 deficiency , Carnitine deficiency , Carnitine-acylcarnitine translocase deficiency, Hypermagnesaemia, Hypoglycemia, Thiamine deficiency, Diabetic ketoacidosis, Hyperosmolar non-ketotic diabetic coma, Hereditary fructose-1-phosphate aldolase deficiency, Fumarase deficiency, Long chain hydroxyacyl-CoA dehydrogenase deficiency, Mitochondrial acetoacetyl-CoA thiolase deficiency
Obstetric/Gynecologic No underlying causes
Oncologic No underlying causes
Opthalmologic No underlying causes
Overdose / Toxicity Amitriptyline, Amoxapine, Antipsychotic agents, Barbiturates, Benzodiazepines, Bromazepam, Bupivacaine, Tetrahydrocannabinol, Buprenorphine, Buspirone, Chlophedianol, Chloral hydrate, Chlorpheniramine, Chlorpromazine, Cinnarizine, Clomipramine, Clonazepam, Clotiapine, Cocaine, Codeine, Cyclobenzaprine, Cycloserine, Dantrolene, Demerol , Demethyldiazepam, Deserpidine, ,Desipramine ,Diamorphine ,Diazepam ,Dichloralphenazone, Diphenhydramine, Diphenidol, Dothiepin, Doxepin , Efavirenz, Eszopiclone, Ethchlorvynol ,Flurazepam , Fluridrazepam, Gabapentin, Gamma hydroxybutyrate, Ganaxolone, General anaesthesia, Glutethimide, Haloperidol, Hydrazine, Hydroxyzine, Imipramine, Inhalational anaesthetics, Iron compounds, Levetiracetam, Levomepromazine, Lidocaine, Local anaesthetia, Lofexidine, Lorazepam, Medazepam, Melatonin, Mephenoxalone, Meprobamate, Methadone, Methaqualone, Methyldopa, Methyprylon, Metoclopramide, Mianserin, Midazolam, Mirtazapine, Morphine, Nabilone, Nitrazepam, Nitrous oxide, Nortriptyline, Novacaine, Olanzapine, Oxazepam, Penicillin, Perazine, Phencyclidine, Phenelzine, Phenobarbital, Pipothiazine, Pizotifen, Pramipexole, Prazepam, Pregabalin, Primidone, Prochlorperazine, Propiomazine, Propofol, Protriptyline, Quetiapine, Ramelteon, Reserpine, Ritalin, Sulfa antibiotics, Temazepam, Thiopentone, Tizanidine, Topiramate, Tricyclic antidepressants, Trifluperidol, Trimipramine, Ultram , Vigabatrin, Zaleplon, Ziconotide, Zolpidem, Zopiclone
Psychiatric No underlying causes
Pulmonary Airway obstruction, Anoxia, Asphyxiation, Pulmonary arteriovenous fistula
Renal / Electrolyte Chronic renal failure, Acute renal failure
Rheum / Immune / Allergy Acute hemorrhagic leukoencephalitis
Sexual No underlying causes
Trauma Acute spinal cord injury, Concussion, Electric shock, Fat embolism, Firearm Injury, Mild Traumatic Brain Injury, Near-drowning, Skull fracture, Epidural haemorrhage, Subdural haemorrhage
Urologic No underlying causes
Dental No underlying causes
Miscellaneous Acute altitude sickness, Decompression sickness, Hyperbaric sickness, Hypothermia, Narcolepsy, Heat stroke, Alcohol withdrawal syndrome

Causes in Alphabetical Order


Differentiating Loss of Consciousness from other Diseases

Differentiating Loss of Consciousness from other Diseases

  • Loss of consciousness should not be confused with the notion of the psychoanalytic unconscious or cognitive processes (e.g., implicit cognition) that take place outside of awareness. Loss of consciousness must not be confused with altered states of consciousness, such as delirium (when the person is confused and only partially responsive to the environment), normal sleep, hypnosis, and other altered states in which the person responds to stimuli.
References

References

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