Confusion is a change in mental status in which a person is not able to think with his or her usual level of clarity. Frequently, confusion leads to the loss of ability to recognize people and or places, or tell time and the date. Feelings of disorientation are common in confusion, and decision-making ability is impaired.
Confusion may arise suddenly or develop gradually over time. Confusion has multiple causes, including injuries, medical conditions, medications, environmental factors, and substance abuse.
Other causes of confusion
- Carbon Monoxide Exposure
- Dissociative Disorders
- Electrolyte Imbalances
- Hospitalization (Particularly in the Elderly)
- Korsakoff Syndrome
- Liver Failure
- Nutritional Deficiencies
- Sleep Deprivation
- Wernicke's Encephalopathy
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Alcohol Abuse: 12 Health Risks of Chronic Heavy Drinking
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Alzheimer's Disease Symptoms & Early Diagnosis
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Parkinson's Disease: Symptoms, Causes, Stages, Treatment
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The Stages of Dementia: Alzheimer's Disease and Aging Brains
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Causes of Confusion
Listeria is a type of bacteria that can cause food poisoning. Listeriosis symptoms include diarrhea, nausea, and fever. Pregnant women are 20 times more likely than other healthy adults to get listeriosis. Listeria infection is treated with antibiotics.
14 Warning Signs and Symptoms of a Stroke FAST
Stroke is a serious medical condition. If you think you or someone you know is having a stroke call 911 immediately. There are two main types of strokes, hemorrhagic and ischemic (the most common type). A hemorrhagic stroke occurs due to a blood vessel rupture in the brain. An ischemic stroke occurs when a blood clot becomes lodged in a blood vessel in the brain, which causes a loss of blood supply to the brain, possibly causing brain tissue death. FAST is an acronym that helps people identify stroke signs and symptoms so they can act fast and call 911. Face drooping, Arm weakness, and Speech difficulty are indicators that a person may be having a stroke and it is Time to seek emergency medical treatment. Additional signs and symptoms of stroke may include weakness, difficulty walking, blurred vision, dizziness, headache, confusion, difficulty speaking, and loss of sensation. Stroke is a major cause of death and disability in the U.S. Early identification and treatment of stroke helps reduce the risk of morbidity and mortality.
Acanthamoeba is an amoeba that lives in dust, soil, and fresh, sea, and brackish water. Acanthamoeba keratitis causes eye pain, a sensation of something in the eye, and blurry vision. Acanthamoeba causes granulomatous encephalitis, leading to seizures, hallucinations, stiff neck, nausea, and vomiting. Diseeminated infection may also result from Acanthamoeba infection.
Alcoholism and Alcohol Abuse
Alcoholism is a disease that includes alcohol craving and continued drinking despite repeated alcohol-related problems, such as losing a job or getting into trouble with the law. It can cause myriad health problems, including cirrhosis of the liver, birth defects, heart disease, stroke, psychological problems, and dementia. Counseling and a few medications can be effective for alcoholism treatment.
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
Anxiety is a feeling of apprehension and fear characterized by symptoms such as trouble concentrating, headaches, sleep problems, and irritability. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. Treatment for anxiety may incorporate medications and psychotherapy.
Are You Too Sick to Work?
When you're not feeling well, it may be difficult to decide whether to stay home or go to school or work. Conditions that are very painful may prevent you from working effectively. Anyone with nausea, vomiting, diarrhea, fever, or dizziness should stay home.
Atrial Fibrillation (AFib) Treatment Drugs
Atrial fibrillation (AFib) is a heart rhythm disorder that causes irregular and often rapid heartbeat. The medications to treat AFib include beta-blockers, blood thinners, and heart rhythm drugs. Atrial fibrillation drugs can cause serious side effects like seizures, vision changes, shortness of breath, fainting, other abnormal heart rhythms, excessive bleeding while coughing or vomiting, blood in the stool, and bleeding into the brain.
Atrial Fibrillation (AFib) vs. Ventricular Fibrillation (VFib)
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm which involves irregular and often rapid beating of the heart. Symptoms may include heart palpitations, dizziness, fainting, fatigue, shortness of breath, and chest pain. Atrial fibrillation treatment may include medication or procedures like cardioversion or ablation to normalize the heart rate. Atrial fibrillation (AFib) and ventricular fibrillation (VFib) are problems with the heart that cause abnormal heart rhythms. Causes of these heart conditions include, heart disease, drugs and medications, excessive alcohol consumption, high cholesterol, advancing age, a diet that contains high levels of animal meat (fat), high blood pressure, stress, stimulants like caffeine, nicotine. Ventricular fibrillation is the more serious of the conditions because if it isn't treated immediately the person will likely die. Symptoms of AFib are confusion, anxiety, fatigue, a fluttering in the chest, and the feeling that you may pass out or faint. Atrial fibrillation is treated with medications, cardioversion therapy, and surgery. If a person with ventricular fibrillation does not seek medical help immediately they will mostly likely suffer from sudden cardiac arrest or sudden death.
Brain Damage: Symptoms, Causes, Treatment
Brain damage causes destruction or deterioration of brain cells. Traumatic brain injury (TBI) and acquired brain injury (ABI) are two kinds of brain damage. Symptoms may include headaches, confusion, memory problems, nausea, and more. Treatment includes patient stabilization and ensuring that blood and oxygen are flowing to the brain. Adequate blood pressure control is also necessary. In cases of severe brain damage, surgery and rehabilitation may be required.
A brain tumor can be either non-cancerous (benign) or cancerous (malignant), primary, or secondary. Common symptoms of a primary brain tumor are headaches, seizures, memory problems, personality changes, and nausea and vomiting. Causes and risk factors include age, gender, family history, and exposure to chemicals. Treatment is depends upon the tumor type, grade, and location.
Brief Psychotic Disorder
Brief psychotic disorder is a short-term mental illness that features psychotic symptoms. There are three forms of brief psychotic disorder. The first occurs shortly after a major stress, the second has no apparent trauma that triggers the illness, and the third is associated with postpartum onset. Symptoms include hallucinations, delusions, unusual behavior, disorientation, changes in eating and sleeping, and speech that doesn't make sense. Treatment typically involves medication and psychotherapy.
The bacteria Capnocytophaga canimorsus is common in the mouths of cats, people, and dogs. People with weak immune systems are at risk for contracting Capnocytophaga infections. Antibiotics can kill this bacteria.
A concussion is a short-lived loss of brain function that is due to head trauma. There are two types of concussion, simple and complex. Symptoms of a concussion include headache, nausea, dizziness, dazed feeling, irritability, and visual symptoms. Physical signs include poor concentration, emotional changes, slurred speech, and personality changes. Concussion is diagnosed with physical examination and testing. Treatment for a concussion in general includes treatment for control of the symptoms and time.
Date Rape Drugs
Date rape drugs such as GHB, rohypnol, and ketamine are sometimes used to assist in a sexual assault. Symptoms and signs of intoxication by one of these drugs depends upon the type of drug ingested.
Dehydration in Adults & Children
Dehydration is the excessive loss of body water. There are a number of causes of dehydration including heat exposure, prolonged vigorous exercise, and some diseases of the gastrointestinal tract. Symptoms of dehydration include headache, lightheadedness, constipation, and bad breath. Treatment for dehydration is to replace lost fluids and electrolytes.
Dementia is defined as a significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. There are several different types of dementia, including cortical, subcortical, progressive, primary, and secondary dementias. Other conditions and medication reactions can also cause dementia. Dementia is diagnosed based on a certain set of criteria. Treatment for dementia is generally focused on the symptoms of the disease.
Depression is an illness that involves the body, mood, and thoughts and affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. The principal types of depression are major depression, dysthymia, and bipolar disease (also called manic-depressive disease).
Diabetic Ketoacidosis (Causes, Symptoms, Treatment, Complications)
Diabetic ketoacidosis (DKA) is a complication of type 1 diabetes that is life threatening. If a person thinks they may have diabetic ketoacidosis they should seek medical care immediately. Diabetic ketoacidosis happens when a person's insulin levels in the blood become dangerously low. Symptoms of diabetic ketoacidosis include dehydration, abdominal pain, confusion, and nausea and vomiting. Diabetic ketoacidosis needs medical treatment. It cannot be treated at home.
Drug Abuse and Addiction
Drug abuse and addiction is a chronic disease that causes drug-seeking behavior and drug use despite negative consequences to the user and those around him. Though the initial decision to use drugs is voluntary, changes in the brain caused by repeated drug abuse can affect a person's self-control and ability to make the right decisions and increase the urge to take drugs. Drug abuse and addiction are preventable.
Encephalitis is a brain inflammation that causes sudden fever, vomiting, headache, light sensitivity, stiff neck and back, drowsiness, and irritability. Treatment may incorporate anticonvulsants and antiviral medications.
Encephalopathy refers to brain disease, damage, or malfunction. Learn about what causes encephalopathy as well as types, symptoms, stages, and treatment.
Fatigue and Exhaustion
Fatigue can be described in various ways. Sometimes fatigue is described as feeling a lack of energy and motivation (both mental and physical). The causes of fatigue are generally related to a variety of conditions or diseases, for example, anemia, mono, medications, sleep problems, cancer, anxiety, heart disease, and drug abuse.Treatment of fatigue is generally directed toward the condition or disease that is causing the fatigue.
Although a fever technically is any body temperature above the normal of 98.6 F (37 C), in practice, a person is usually not considered to have a significant fever until the temperature is above 100.4 F (38 C). Fever is part of the body's own disease-fighting arsenal; rising body temperatures apparently are capable of killing off many disease-producing organisms.
Head Injury (Brain Injury)
In the United States, head injuries are one of the most common causes of death and disability. Head injuries due to bleeding are generally classified by the location of the blood within the skull, these include epidural hematoma, subdural hematoma, subarachnoid bleed, intracranial bleed, sheer injury, edema, and skull fracture. Some common symptoms of a head injury include vomiting, bleeding from the ear, speech difficulties, paralysis, difficulty swallowing, and body numbness. Treatment of a head injury depends on the type and severity of the injury.
Heat stroke (heatstroke or sun stroke) is a form of hyperthermia. Heat stroke is a true medical emergency that can be fatal if not promptly and properly treated. Symptoms of heat stroke include high body temperature, absence of sweating, hot red or flushed dry skin, rapid pulse, difficulty breathing, strange behavior, hallucinations, confusion, agitation, disorientation, seizure, and coma. A victim of heat stroke must receive immediate treatment to avoid permanent organ damage.
Hypercalcemia (Elevated Calcium Levels)
Hypercalcemia is a condition in which calcium levels in the blood are elevated. Hypercalcemia is associated with other conditions such as hyperparathyroidism, lung cancer, breast cancer, kidney failure, and elevated levels of vitamin D. Symptoms of hypercalcemia include constipation, nausea, abdominal pain, and kidney stones. Treatment depends on the cause of hypercalcemia.
Hypothermia or extreme exposure to cold can be classified as either accidental hypothermia (unintentional cold exposure) or intentional hypothermia (generally induced for a medical procedure). Hypothermia is caused by exposure to extremely cold temperatures. Risk factors for hypothermia include cold exposure and/or certain medical conditions. Symptoms of hypothermia include shivering; increased heart rate, breathing rate, and blood pressure; apathy, confusion, slurred speech, no reflexes, and dilated pupils. Medical attention is generally necessary to treat hypothermia.
Hypothyroidism is any state in which thyroid hormone production is below normal. Normally, the rate of thyroid hormone production is controlled by the brain by the pituitary gland. Hypothyroidism is a very common condition and the symptoms of hypothyroidism are often subtle but may include constipation, memory loss, hair loss, and depression. There are a variety of causes of hypothyroidism, and treatment depends on the cause.
Hypoxia is a condition in which the normal concentration of oxygen in the blood is not enough for normal life functions. Symptoms of hypoxia and/or hypoxemia may be acute such as fast heart rate, rapid breathing, and shortness of breath; or severe symptoms include confusion, the inability to communicate, coma, and sometimes death. Treatment of hypoxia and/or hypoxemia is to provide supplemental oxygen to the body as soon as possible.
Internal bleeding is a serious consequence of trauma and can be life-threatening, requiring immediate medical attention. Learn about signs, causes, and treatment.
Is Sepsis Contagious?
Sepsis is a potentially life-threatening infection that may be caused by bacteria, fungi, viruses, or parasites. Sepsis spreads within the body from the infection site. Treatment of sepsis typically involves the administration of intravenous medications.
Jet lag (desynchonosis) is a temporary disorder that results from travel across time zones. Symptoms include anxiety, constipation, headache, nausea, dehydration, diarrhea, confusion, sweating, irritability, and even memory loss.
Kidney (Renal) Failure
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss, dehydration, or medication. Some of the renal causes of kidney failure include sepsis, medications, rhabdomyolysis, multiple myeloma, and acute glomerulonephritis. Post renal causes of kidney failure include bladder obstruction, prostate problems, tumors, or kidney stones.Treatment options included diet, medications, or dialysis.
Lassa fever is a viral hemorrhagic fever that causes flu-like symptoms. Ribavirin is the standard treatment for Lassa fever. Hearing loss is a common complication of Lassa fever.
Lewy Body Dementia (Dementia with Lewy Bodies)
Lewy body dementia (LBD or dementia with Lewy bodies) is one the most common causes of dementia. There are two types of LBD: 1) dementia with Lewy bodies, and 2) Parkinson's disease dementia. Symptoms of LBD are changes in a person's ability to think, movement problems, and sleep disorders. Treatment of LBD includes lifestyle changes, management of symptoms, palliative care, and medications to manage symptoms.
Low Blood Sugar (Hypoglycemia)
Low blood sugar or hypoglycemia occurs when blood sugar is dangerously low and is often complication of type 1 and type 2 diabetes. Learn about symptoms, dangers, and treatment.
Lyme disease is a bacterial illness, which is spread by ticks when they bite the skin. Initially the disease affects the skin causing a reddish rash associated with flu-like symptoms. It takes weeks to months after the initial redness of the skin for its effects to spread throughout the body. Lyme disease can be treated with antibiotics. Lyme disease can be prevented by using tick avoidance techniques.
Postpartum depression is a form of depression that occurs within a year after delivery. It is thought that rapid hormone changes after childbirth may lead to depression. Symptoms of postpartum depression include crying a lot, headaches, chest pains, eating too little or too much, sleeping too little or too much, withdrawal from friends and family, and feeling irritable, sad, hopeless, worthless, guilty, and overwhelmed. Treatment typically involves talk therapy and medication.
Powassan Virus Disease
Powassan (POW) virus disease is a rare tick-borne disease that causes symptoms such as confusion, memory problems, fever, headache, vomiting, and seizures. POW virus treatment focuses on supportive care that aims to reduce symptoms. There is no medication or cure for POW virus disease.
Psychotic disorders are a group of serious illnesses that affect the mind. Different types of psychotic disorders include schizophrenia, schizoaffective disorder, schizophreniform disorder, brief psychotic disorder, shared psychotic disorder, delusional disorder, substance-induced psychotic disorder, paraphrenia, and psychotic disorders due to medical conditions.
Reye's syndrome (RS or Reye syndrome) is a sudden, sometimes fatal, disease of the brain with degeneration of the liver. Reye syndrome is associated with giving children medications containing aspirin. Symptoms include vomiting, listlessness, irritability or combativeness, confusion, delirium, delusions, convulsions, and loss of consciousness. Treatment depends on early diagnosis and focuses on protecting the brain against irreversible damage by reducing brain swelling, reversing the metabolic injury, preventing complications in the lungs, and anticipating cardiac arrest.
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Rocky Mountain Spotted Fever (RMSF)
Rocky Mountain spotted fever is a tick-borne disease that causes symptoms and signs such as fever, rash, headache, and muscle aches. The antibiotic doxycycline is the standard treatment for Rocky Mountain spotted fever.
Schizophrenia is a disabling brain disorder that may cause hallucinations and delusions and affect a person's ability to communicate and pay attention. Symptoms of psychosis appear in men in their late teens and early 20s and in women in their mid-20s to early 30s. With treatment involving the use of antipsychotic medications and psychosocial treatment, schizophrenia patients can lead rewarding and meaningful lives.
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy. Treatment of epilepsy (seizures) depends upon the cause and type of seizures experienced.
Sepsis (Blood Poisoning)
Sepsis (blood poisoning) is a potentially deadly infection with signs and symptoms that include elevated heart rate, low or high temperature, rapid breathing and/or a white blood cell count that is too high or too low and has more than 10% band cells. Most cases of sepsis are caused by bacterial infections, and some cases are caused by fungal infections. Treatment requires hospitalization, IV antibiotics, and therapy to treat any organ dysfunction.
Septic shock is a system-wide infection that causes low blood pressure and organ failure. Symptoms and signs include vomiting, nausea, anxiety, confusion, fever, shakes, chills, rapid heart rate, and increased breathing rate. Treatment may incorporate intravenous fluids and antibiotics and possible intubation.
What is shock? A life-threatening condition with symptoms like low blood pressure, weakness, shallow breathing, clammy skin, fainting, anxiety, confusion, and chest pain. Learn about causes, types, and treatment.
Sick Building Syndrome
Multiple chemical sensitivity (MCS) or also referred to as sick building syndrome or environmental illness is the name given by some to a condition in which various symptoms reportedly appear after a person has been exposed to any of a wide range of chemicals. The exposure may occur as a major event, such as a chemical spill, or from long-term contact with low-levels of chemicals, such as in an office with poor ventilation. As a result of exposure, people with MCS (sick building syndrome) develop sensitivity and have reactions to the chemicals even at levels most people can tolerate.
Sleep apnea is defined as a reduction or cessation of breathing during sleep. The three types of sleep apnea are central apnea, obstructive apnea (OSA), and a mixture of central and obstructive apnea. Central sleep apnea is caused by a failure of the brain to activate the muscles of breathing during sleep. OSA is caused by the collapse of the airway during sleep. OSA is diagnosed and evaluated through patient history, physical examination and polysomnography. There are many complications related to obstructive sleep apnea. Treatments are surgical and non-surgical.
Group A streptococcal infections are caused by group A Streptococcus, a bacteria that causes a variety of health problems, including strep throat, impetigo, cellulitis, erysipelas, and scarlet fever. There are more than 10 million group A strep infections each year.
A stroke is an interruption of the blood supply to part of the brain caused by either a blood clot (ischemic) or bleeding (hemorrhagic). Symptoms of a stroke may include weakness, numbness, double vision or vision loss, confusion, vertigo, difficulty speaking, or understanding speech. A physical exam, imaging tests, neurological exam, and blood tests may be used to diagnose a stroke. Treatment may include administration of clot-busting drugs, supportive care, and in some instances, neurosurgery. The risk of stroke can be reduced by controlling high blood pressure, high cholesterol, diabetes, and stopping smoking.
Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
Syndrome of inappropriate antidiuretic hormone (SIADH) is common in older individuals and happens when too much antidiuretic hormone releases and causes water retention and a low sodium level. There are several causes of SIADH. Symptoms include seizures, irritability, elevated systolic blood pressure, and hyponatremia, among others. Treatment involves restricting fluids, treating the underlying cause, and taking medications to decrease the antidiuretic hormone's effect on the kidneys.
Teen Drug Abuse
Drugs commonly abused by teens include tobacco products, marijuana, cold medications, inhalants, depressants, stimulants, narcotics, hallucinogens, PCP, ketamine, Ecstasy, and anabolic steroids. Some of the symptoms and warning signs of teen drug abuse include reddened whites of eyes, paranoia, sleepiness, excessive happiness, seizures, memory loss, increased appetite, discolored fingertips, lips or teeth, and irritability. Treatment of drug addiction may involve a combination of medication, individual, and familial interventions.
Ticks (Tick Bites)
Ticks are known transmitters of disease to humans and animals. Tick-borne diseases include Lyme disease, Rocky Mountain spotted fever, Q fever, tularemia, babesiosis, and Southern tick-associated rash illness. Infected ticks spread disease once they've bitten a host, allowing the pathogens in their saliva and mouth get into the host's skin and blood. Tick bites are typically painless, but the site of the bite may later itch, burn, turn red, and feel painful. Individuals allergic to tick bites may develop a rash, swelling, shortness of breath, numbness, or paralysis. Tick bite treatment involves cleaning and applying antibiotic cream.
Toxic Shock Syndrome (TSS)
Toxic shock syndrome (TSS) is an infection caused by Streptococcus or Staphylococcus. Toxic shock syndrome symptoms include low blood pressure, fever, and a rash with peeling skin. Treatment involves IV fluids to treat the shock, IV antibiotics, cleaning infected wounds, and hospitalization in the intensive care for other assorted treatments.
Transient Ischemic Attack (TIA, Mini-Stroke)
When a portion of the brain loses blood supply, through a blood clot or embolus, a transient ischemic attack (TIA, mini-stroke) may occur. If the symptoms do not resolve, a stroke most likely has occurred. Learn the symptoms, risk factors, and treatment for a transient ischemic attack.
Vancomycin-Resistant Enterococci (VRE)
Vancomycin-resistant enterococci (VRE) infection is the most common type of infection acquired by patients while hospitalized. Patients at risk for VRE are those who are already ill, and hospitalized, including individuals with diabetes, elderly, ICU patients, kidney failure patients, or patients requiring catheters. Enterococci can survive for months in the digestive tract and female genital tract. Other risk factors for acquiring VRE include those how have been previously treated with vancomycin and combinations of other antibiotics. Treatment of VRE is generally with other antibiotics other than vancomycin. Prevention of VRE can be achieved by proper hand hygiene.
West Nile Virus
West Nile virus (West Nile encephalitis) is a brain infection caused by a virus. People become infected with the virus after they're bitten by a mosquito that has fed off of a bird that's infected with the West Nile virus. Symptoms in humans include fever, headache, rash, body ache, and swollen lymph nodes. Treatment for a West Nile virus infection involves supportive care.
Yellow fever is an infectious disease transmitted by infected mosquitoes. Side effects are rare with the yellow fever vaccine. Symptoms include fever, chills, back pain, nausea, vomiting, and headache. Treatment is aimed at relieving symptoms.
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