Fainting, also referred to as blacking out, syncope, or temporary loss of consciousness has many causes. Often a person will have signs or symptoms prior to the fainting episode. Diagnosis and treatment depends upon the cause of the fainting or syncope episode. Read more: Fainting (Syncope) Article
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Low Blood Pressure (Hypotension): Symptoms, Signs, Causes
What is low blood pressure (hypotension)? Explore low blood pressure causes, symptoms, and signs. Discover what is considered low...
Dehydration: Causes, Symptoms & Signs
Do you know the signs of dehydration? Dehydration can be mild or life-threatening. Learn causes, symptoms, treatments, and...
What Happens After a Stroke? Signs, Symptoms, Types
What is a stroke? Learn about the different types of stroke, as well as many symptoms like sudden numbness or weakness,...
Fainting: What Makes You Faint?
Find out how dehydration, low blood pressure, arrhythmia, and other problems can make you feel woozy and even faint.
Related Disease Conditions
Low Blood Pressure (Hypotension)
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, and fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.
Heat Exhaustion (First Aid Tips)
Heat exhaustion is a milder form of heat-related illness that can develop after several days of exposure to high temperatures and inadequate or unbalanced replacement fluids. Warning signs of heat exhaustion include heavy sweating, paleness, muscle cramps, tiredness, weakness, dizziness, headache, nausea or vomiting, and fainting. A person suffering from heat exhaustion should stop the activity are doing, move to a cooler environment, and rehydrate with liquids, for example, water or sports drinks. Complications of heat exhaustion are dehydration, muscle weakness, nausea, and vomiting. Heat exhaustion can progress to heat stroke (a medical emergency) if not treated.
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.
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.
Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
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.
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.
Dizziness is a symptom that often applies to a variety of sensations including lightheadedness and vertigo. Causes of dizziness include low blood pressure, heart problems, anemia, dehydration, and other medical conditions. Treatment of dizziness depends on the cause.
Pregnancy (Week by Week, Trimesters)
Signs and symptoms of pregnancy vary by stage (trimester). The earliest pregnancy symptom is typically a missed period, but others include breast swelling and tenderness, nausea and sometimes vomiting, fatigue, and bloating. Second trimester symptoms include backache, weight gain, itching, and possible stretch marks. Third trimester symptoms are additional weight gain, heartburn, hemorrhoids, swelling of the ankles, fingers, and face, breast tenderness, and trouble sleeping. Eating a healthy diet, getting a moderate amount of exercise, also are recommended for a healthy pregnancy. Information about the week by week growth of your baby in the womb are provided.
Atrial Flutter vs. Atrial Fibrillation
Atrial flutter and atrial fibrillation (AFib) are two types of a heart problem called atrial tachycardia. Both of these conditions involve the heart's electrical activity, but they are not the same disease. Both diseases are serious and need medical treatment. Common symptoms of these diseases are similar and include: Fatigue Blurry vision Lightheadedness Palpitations Feeling like you may faint Serious symptoms of both conditions are similar and include: Fainting Sweating Severe shortness of breath Chest pain Atrial flutter and AFib are heart conditions that require medical diagnosis (ECG) and treatment by a doctor or other medical health-care professional.
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.
What Can Trigger Vertigo?
Vertigo is the sensation of spinning or rocking, even when someone is at rest. Vertigo may be caused by a problem in the brain or spinal cord or a problem within in the inner ear. Head injuries, certain medications, and female gender are associated with a higher risk of vertigo. Medical history, a physical exam, and sometimes an MRI or CT scan are required to diagnose vertigo. The treatment of vertigo may include medication, special exercises to reposition loose crystals in the inner ear, or exercises designed to help the patient re-establish a sense of equilibrium. Controlling risk factors for stroke (blood pressure, weight, cholesterol, and blood glucose) may decrease the risk of developing vertigo.
Parkinson's disease is a slowly progressive neurological disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40.
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.
Heart Attack (Myocardial Infarction)
A heart attack occurs when a blood clot completely obstructs a coronary artery supplying blood to the heart muscle. Learn about warning signs, causes, complications, risk factors, and treatment.
Premature Ventricular Contractions (PVCs)
Premature ventricular contractions (PVC) are premature heartbeats originating from the ventricles of the heart. PVCs are premature because they occur before the regular heartbeat. There are many causes of premature ventricular contractions to include: heart attack, high blood pressure, congestive heart failure, mitral valve prolapse, hypokalemia, hypoxia, medications, excess caffeine, drug abuse, and myocarditis.
Atrial Fibrillation (AFib)
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.
Mitral Valve Prolapse
Mitral valve prolapse (MVP), also called "click murmur syndrome" and "Barlow's syndrome," is the most common type of heart valve abnormality. Usually, people with mitral valve prolapse have no signs and symptoms; however, if the prolapsed valve is severe, symptoms may appear. When symptoms of severe mitral valve prolapse do appear, they may include, fatigue, palpitations, chest pain, anxiety, migraine headaches, and pulmonary edema. Echocardiography is the most useful test for mitral valve prolapse. Most people with mitral valve prolapse need no treatment. However, if the valve prolapse is severe, treatment medications or surgery may be necessary to repair the heart valve.
An arrhythmia is an abnormal heart rhythm. With an arrhythmia, the heartbeats may be irregular or too slow (bradycardia), to rapid (tachycardia), or too early. When a single heartbeat occurs earlier than normal, it is called a premature contraction.
Arrhythmias (Abnormal Heart Rhythms)
Heart rhythm disorders vary from minor palpitations, premature atrial contractions (PACs), premature ventricular contractions (PVCs), sinus tachycardia, and sinus bradycardia, to abnormal heart rhythms such as tachycardia, ventricular fibrillation, ventricular flutter, atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT), Wolf-Parkinson-White syndrome, brachycardia, or heart blocks. Treatment is dependent upon the type of heart rhythm disorder.
Is POTS a Serious Condition?
Postural orthostatic tachycardia syndrome (POTS) is a syndrome characterized by increased heart rate (tachycardia), a fall in blood pressure (hypotension) and giddiness when standing (orthostatic). In POTS, the symptoms occur because the heart does not receive sufficient blood supply when the person stands upright.
Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on one side of the head, and sometimes nausea and vomiting. The exact cause of migraine headaches is not known. Triggers for migraine headaches include certain foods, stress, hormonal changes, strong stimuli (loud noises), and oversleeping. Treatment guidelines for migraines include medicine, pain management, diet changes, avoiding foods that trigger migraines, staying hydrated, getting adequate sleep, and exercising regularly. Prevention of migraine triggers include getting regular exercise, drinking water daily, reducing stress, and avoiding trigger foods.
Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are benign, while others are more serious. Palpitations are diagnosed by taking the patient history and by performing an EKG or heart monitoring along with blood tests. An electrophysiology study may also be performed. Treatment of palpitations may include lifestyle changes, medication, ablation, or implantation of a pacemaker. The prognosis if palpitations depends on the underlying cause.
Orthostatic hypotension symptoms include: LightheadednessWeaknessBlurred vision Syncope or passing out Causes of orthostatic hypotension include: Dehydration, Anemia, Medication Blood loss Low blood pressure Heat related illnesses Parkinson's disease Diabetes Treatment of orthostatic hypotension depends on the underlying cause.
Cyclic Vomiting Syndrome (CVS)
Cyclic vomiting syndrome is a condition in which affected individuals have severe nausea and vomiting that come in cycles. Researchers believe that cyclic vomiting syndrome and migraine headaches are related. Triggers of cyclic vomiting syndrome are emotional stress and infections. People with cyclic vomiting syndrome are at an increased risk of dehydration. Cyclic vomiting syndrome is difficult to diagnose. Treatment varies from person to person, but is generally directed toward relief of the symptoms of the condition.
What Are the Symptoms of Dysautonomia?
Dysautonomia is also called autonomic dysfunction or autonomic neuropathy. The symptoms of dysautonomia include fainting, dizziness, balance problems, brain fog, chest pain, palpitations, trouble swallowing, sleep problems and other issues.
Balance is a state of body equilibrium or stability. We often take for granted how dependent we are on a healthy balance system. When the system breaks down, however, patients will describe symptoms such as dizziness, vertigo, lightheadedness, or motion sickness.
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.
Atrial Fibrillation (AFib) Symptoms and Signs
Atrial fibrillation or AFib is a type of heart rhythm abnormality. Early warning signs and symptoms of atrial fibrillation include chest pain, palpitations, shortness of breath, and lightheadedness. Treatment for atrial fibrillation includes medical procedures, surgery, and medication.
POTS (POT Syndrome, Postural Orthostatic Tachycardia Syndrome)
POT syndrome (POTS, postrual orthostatic tachycardia syndrome) is a nervous system disorder that causes lightheadedness and fainting when a person stands up. Treatment may include increasing blood volume and regulating circulatory problems that are responsible for the disorder.
Aortic Valve Stenosis (Symptoms, Causes, Surgery)
Aortic valve stenosis is an abnormal narrowing of the aortic valve of the heart. The causes of aortic stenosis are wear and tear of the valve in the elderly, congenital, or scarring or scarring of the aortic valve from rheumatic fever. Symptoms include angina, fainting, and shortness of breath. Treatment is dependant upon the severity of the condition.
Hyperthermia (Heat-Related Illness)
Heat-related illness include heat rash, cramps, exhaustion, stroke, and sunburn. Treatment of heat related illnesses depend on the condition, but symptoms may include headache, nausea, vomiting, dizziness, fainting, seizures, and coma. Heat stroke is a medical emergency, and may result in death if not treated promptly. Heat exhaustion may lead to heat stroke if not treated properly.
Munchausen syndrome is a factitious disorder and attention-seeking syndrome in which an individual pretends to have physical or psychological symptoms in order to gain attention. Symptoms and signs vary from heart symptoms, chest pain, and fainting to ear problems and hallucinations. Sufferers tend to seek help from multiple care providers, seem overly pleased at being subjected to tests and procedures, and have vague symptoms that are inconsistent with test results. There is no particular treatment approach that is consistently effective in treating Munchausen syndrome.
Paroxysmal Supraventricular Tachycardia (PSVT)
Paroxysmal supraventricular tachycardia (PSVT) is an abnormal conduction of electricity in particular areas of the heart. PSVT was referred to at one time as paroxysmal atrial tachycardia or PAT, however, the term PAT is reserved for as specific heart condition. Symptoms of PSVT include weakness, shortness of breath, chest pressure, lightheadedness, and palpitations. PSVT is treated with medications or procedures that return the heart to its normal electrical pattern.
Sudden Cardiac Arrest
Sudden cardiac arrest is an unexpected, sudden death caused by sudden cardiac arrest (loss of heart function). Causes and risk factors of sudden cardiac arrest include (not inclusive) abnormal heart rhythms (arrhythmias), previous heart attack, coronary artery disease, smoking, high cholesterol,Wolff-Parkinson-White Syndrome, ventricular tachycardia or ventricular fibrillation after a heart attack, congenital heart defects, history of fainting, heart failure, obesity, diabetes, and drug abuse. Treatment of sudden cardiac arrest is an emergency, and action must be taken immediately.
Pulmonary hypertension is elevated pressure in the pulmonary arteries that carry blood from the lungs to the heart. The most common symptoms are fatigue and difficulty breathing. If the condition goes undiagnosed, more severe symptoms may occur. As pulmonary hypertension worsens, some people with the condition have difficulty performing any activities that require physical exertion. While there is no cure for pulmonary hypertension, it can be managed and treated with medications and supplemental oxygen to increase blood oxygen levels.
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.
Moyamoya disease is an inherited (genetic) progressive cerebrovascular disorder caused by arteries that are blocked at the base of the brain. Moyamoya means "puff of smoke" in Japanese. Signs and symptoms of Moyamoya disease in adults include fainting, and vision problems, and in children included may include headaches and speech problems. There are 6 stages of Moyamoya disease. Surgery is the preferred treatment for the disease, and there is no cure for Moyamoya disease, and it can be fatal.
Chagas disease is an infection caused by the T. cruzi parasite. Symptoms of Chagas disease include rash, swollen lymph nodes, fever, fatigue, nausea, vomiting, and the Romaña sign. An ELISA test is used to diagnose Chagas disease. Treatment depends upon the phase of the disease and the patient's age.
Heart Attack Treatment
A heart attack involves damage or death of part of the heart muscle due to a blood clot. The aim of heart attack treatment is to prevent or stop this damage to the heart muscle. Heart attack treatments included medications, procedures, and surgeries to protect the heart muscle against injury.
Hypertrophic cardiomyopathy (HCM) affects many people today. Many people with HCM have no symptoms or only minor symptoms, and live a normal life. Other people develop symptoms, which progress and worsen as heart function worsens.
Pregnancy Changes and Body Discomforts
Pregnancy can bring challenges like weight gain, stretch marks, varicose veins, heartburn, constipation, hemorrhoids, problems sleeping, and wondering if it is safe to have sex while pregnant. Learn how to manage and move through these challenges during pregnancy.
Drug Allergy (Medication Allergy)
Drug or medication allergies are caused when the immune system mistakenly creates an immune response to a medication. Symptoms of a drug allergic reaction include hives, rash, itchy skin or eyes, dizziness, nausea, diarrhea, fainting, and anxiety. The most common drugs that people are allergic to include penicillins and penicillin type drugs, sulfa drugs, insulin, and iodine. Treatment may involve antihistamines or corticosteroids. An EpiPen may be used for life-threatening anaphylactic symptoms.
Heart Valve Disease
Heart valve disease occurs when the heart valves do not work the way they should. Symptoms of valve disease include shortness of breath, weakness or dizziness, discomfort in your chest, palpitations, swelling of your ankles, feet or abdomen, and rapid weight gain.
Insect Sting Allergies
The majority of stinging insects in the United States are from bees, yellow jackets, hornets, wasps, and fire ants. Severity of reactions to stings varies greatly. Avoidance and prompt treatment are essential. In selected cases, allergy injection therapy is highly effective.
Dilated Cardiomyopathy is a condition where the heart's ability to pump blood is decreased because the heart's main pumping chamber is enlarged and weakened. Symptoms of dilated cardiomyopathy include chest pain, heart failure, swelling of the lower extremities, fatigue, weight gain, fainting, palpitations, dizziness and blood clots.
Preeclampsia (Pregnancy Induced Hypertension)
Preeclampsia is related to increased blood pressure and protein in the mother's urine. Preeclampsia typically begins after the 20th week of pregnancy. When preeclampsia causes seizures, it is termed "eclampsia" and is the second leading cause of maternal death of in the US. Preeclampsia is the leading cause of fetal complications. Risk factors for preeclampsia include high blood pressure, obesity, multiple births, and women with preexisting medical conditions such as diabetes, kidney disease, rheumatoid arthritis, lupus, or scleroderma. Pregnancy planning and lifestyle changes may reduce the risk of preeclampsia during pregnancy.
How Do You Get Vasovagal Syncope?
Vasovagal syncope is the medical term for fainting. It occurs when your body has a sudden drop in heart rate or blood pressure, leading to reduced blood flow to your brain and a temporary loss of consciousness.
Restrictive cardiomyopathy, the rarest form of cardiomyopathy, is a condition in which the walls of the lower chambers of the heart (the ventricles) are abnormally rigid and lack the flexibility to expand as the ventricles fill with blood. The pumping or systolic function of the ventricle may be normal but the diastolic function (the ability of the heart to fill with blood) is abnormal. Therefore, it is harder for the ventricles to fill with blood, and with time, the heart loses the ability to pump blood properly, leading to heart failure.
Treatment & Diagnosis
Medications & Supplements
- Beta Blockers
- metoprolol (Lopressor, Toprol XL)
- amlodipine (Norvasc)
- propranolol, Inderal, Inderal LA, Innopran XL
- diltiazem (Cardizem, Cardizem CD, Cardizem LA, Tiazac, Cartia XT, Diltzac, Dilt-CD, and several oth)
- Calcium Channel Blockers (CCBs)
- verapamil (Calan, Verelan, Verelan PM [Discontinued: Isoptin, Isoptin SR, Covera-HS])
- aromatic ammonia - inhalation
Prevention & Wellness
- AHA News: Millions Unaware of Common Heart Attack Symptoms
- AHA News: 24-Year-Old's Fainting Was a Clue to Her Fatal Heart Condition
- Intense Gaming Can Trigger Irregular Heartbeat, Fainting in Some Players
- Health Tip: First Aid for Fainting
- Astronauts: Exercise More in Space, Faint Less on Earth
- Do You Have the 'Fainting Gene'?
- New Theory Sheds Light on Leonardo da Vinci's Artistic Decline
- FDA Orders Label Warning on Alcohol Use With 'Female Viagra'
- AHA News: Two Young Moms Bond Over Heart Failure, Transplant Experiences
- You've Fainted. How Long Do You Need to Stay in the ER?
- How Long Should Fainting Patients Be Monitored?
- Health Tip: If You Feel Faint
- What to Do If You Think You're Having a Heart Attack
- Medical Groups Raise Blood Pressure Rx Threshold for Healthy Adults Over 60
- Clots May Be the Cause of Fainting in Some Elderly
- First Days of Preseason Practice Pose Big Heat Risks for College Football Players
- Health Tip: Warning Signs of Nerve Damage
- Heat Waves Pose Big Health Threats
- Guidelines Stop Heat Stroke Deaths in High School Athletes
- Elderly Benefit From Intensive Blood Pressure Treatment
- More Support for Aggressive Blood Pressure Treatment for Elderly
- Car Crash Risk May Nearly Double in People Prone to Fainting
- Indoor Tanning Tied to Burns, Fainting, Eye Injuries: Study
- Many Kids Exposed to Unneeded X-Rays, Study Finds
- Mutant Gene Spurs Dangerous Heart Condition in Newfoundland Dogs: Study
- Poorly Understood Disorder Disables Many Younger Women
- Living a Full Life, Irregular Heartbeat and All
- Farxiga Approved for Type 2 Diabetes
- Weight Loss Can Combat Irregular Heart Beat, Study Says
- Health Tip: Will a Pacemaker Help Me?
- Training in the Heat
- Did Extreme Cola Habit Cause Woman's Irregular Heartbeat?
- One in 600 Flights Involves Medical Emergency, Study Says
- Health Tip: Why Did I Faint?
- Hillary Clinton Plans to Return to Work Next Week
- Fainting in Healthy People May Be First Sign of Heart Trouble
- Heart Drug Digoxin Tied to Higher Death Risk for Some Patients
- Health Tip: Do You Have a Heart Murmur?
- Fainting Spells Often Tied to Too Many Meds at Once: Study
- Post-Flight Fainting May Signal Dangerous Blood Clot: Study
- HPV Vaccine Not Linked to Promiscuity in Girls
- HPV Vaccine Found Safe in Large Study
- Son's Real-Life Drama Leads Comedy Queen to Medical Role
- Fainting Might Run in Families, Twin Study Finds
- Fainting May Run in the Family
- Health Tip: Heed the Warning Signs of Heat Exhaustion
- Drive-Through Flu Shot a Safe Bet: Study
- It's Not So Much the Heat, It's the Lack of Power
- Health Tip: Are Your Child's Tantrums Dangerous?
- Health Tip: Understanding Adult Dehydration
- Summer's Heat May Enflame Hives
- Less Invasive Heart Valve Replacement Works for Elderly: Study
- Is Your Child Playing the 'Choking Game'?
- Longer Use of Alzheimer's Drug May Help Patients
- Family Tree May Aid Treatment of Inherited Heart Disorders
- Students Report Playing Dangerous 'Choking Game'
- New Guidelines on Frequent Cause of Sudden Death in Athletes
- Report: Vaccines Generally Safe, Cause Few Health Problems
- Drug Combo May Help Treat Kids With ADHD
- People With Signs of Parkinson's Wait to See Doctor