- Fainting (vasovagal syncope)
Before fainting, you might feel lightheaded, warm, nausea, a cold sweat, or have tunnel vision.
- Middle ear infection
A middle ear infection puts pressure on the eardrum, causing pain and, sometimes, hearing loss.
- Labyrinthitis
Labyrinthitis, an infection and swelling in the inner ear, and may cause vertigo or hearing loss.
- Medication reaction or side-effect
Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more.
- Dehydration (Children)
Dehydration, or not getting enough fluid, causes dry and sticky mouth, tearless crying, and more in children.
- Dehydration (Adult)
Dehydration, or not getting enough fluid, causes low blood pressure, weakness, dizziness, fatigue, and nausea.
- Atrial fibrillation
Atrial fibrillation is a heart condition that causes heart palpitations, confusion, dizziness and more.
- Heart rhythm disorder
Some heart rhythm disorders can cause a fluttering in the chest, shortness of breath, chest pain or dizziness.
- Heat exhaustion
Heat exhaustion causes intense thirst, heavy sweating, pale, cool, and moist skin, muscle cramps, and more.
- Low blood sugar (hypoglycemia)
Low blood sugar, or low glucose levels, causes shakiness, anxiety, clammy skin, irritability, hunger, and more.
- Supraventricular tachycardia
Supraventricular tachycardia is fast heart rhythm starting in one of the upper chambers of the heart.
- Anemia
Anemia, a lack of red blood cells, can cause fatigue, pale skin, weakness, dizziness, headache and more.
- Drug overdose
A drug overdose can be fatal and causes sleepiness, confusion, coma, vomiting, and other symptoms.
- Hyperventilation
Hyperventilation is rapid or shallow breathing usually caused by stress or anxiety.
- Insulin reaction (hypoglycemia)
An insulin reaction is the result of low blood sugar and causes anxiety, hunger, shaking, dizziness, and more.
- Pulmonary hypertension
Pulmonary hypertension can cause shortness of breath, a fast heart rate, or lightheadedness.
- Benzodiazepine abuse
Benzodiazepines are prescription medications that cause drowsiness, dizziness, blurred vision, and more.
- Aortic stenosis
Aortic stenosis is a condition of the heart causing shortness of breath, dizziness, or chest pain.
- Aspirin poisoning
Aspirin poisoning is a medical emergency and can cause nausea, vomiting, drowsiness and more.
- Transient global amnesia
Transient global amnesia is a sudden loss of memory. Symptoms usually last for hours and then memory returns.
- Dementia with Lewy bodies
Dementia with Lewy bodies is a brain disorder that causes problems managing memory and movement.
- Aortic regurgitation
Aortic regurgitation, when the aortic valve doesn't close completely, can cause severe heart symptoms.
- Epilepsy (complex partial seizures)
During complex partial seizures, people lose consciousness briefly.
- Short-acting sedative use
The symptoms of short-acting sedatives include drowsiness, vertigo, muscle weakness, double vision, and more.
- Generalized anxiety disorder
Generalized anxiety disorder is a condition in which a person has nearly constant anxiety.
- Diabetes, type 2
Diabetes can make you feel hungry, tired, or thirsty; you may urinate more than normal and have blurry vision.
- Benign paroxysmal positional vertigo (BPPV)
Benign paroxysmal positional vertigo is usually a temporary condition that affects balance and causes vertigo.
- Panic attack
When someone has a panic attack, that person feels a sudden, intense fear that can't be controlled.
- Encephalitis
Encephalitis is swelling and inflammation of the brain from an infection causing sleepiness, fever, and more.
- Low blood pressure (hypotension)
Low blood pressure, or hypotension, can make you feel lightheaded and dizzy
- Atrial flutter
Atrial flutter is an abnormality of the heart's rhythm that causes rapid and sometimes irregular heartbeats.
- Tetralogy of Fallot
Tetralogy of Fallot is a combination of heart defects causing bluish skin, trouble breathing, and more.
- Hypothyroidism (adult)
Hypothyroidism your body functions slow down, making you gain weight and feel tired all the time.
- Narcotic abuse
Narcotic abuse can cause fatigue, shallow breathing, anxiety, euphoria, vomiting, confusion, and constipation.
- Night terrors
Night terrors are a sleep disorder that cause people to partially wake up confused and terrified.
- Intoxication
Symptoms of intoxication include euphoria, slowed reaction time, dizziness, confusion, numbness, and more.
- Epilepsy (temporal lobe)
Epilepsy is a condition marked by seizures.
- Epilepsy (absence or petit mal seizures)
Petit mal or absence epileptic seizures cause staring spells or chewing motions.
- Epilepsy (simple partial seizures)
During simple partial epileptic seizures, people remain fully conscious, able to respond to external stimuli.
- Anemia, iron deficiency
Anemia , a lack of red blood cells, can cause fatigue, pale skin and gums, brittle nails, irritability, and more.
- Barbiturate abuse
Barbiturates are a type of prescription sedative in which even a slight overdose can cause coma or death.
- Carbon monoxide poisoning
Carbon monoxide poisoning can be fatal, symptoms include headache, dizziness, nausea, and vomiting.
- Head injury
Symptoms of a head injury vary but include headache, nausea, dizziness, memory problems, confusion, and more.
- Dementia in head injury
Dementia resulting from a head injury may cause memory problems, difficulty speaking, and personality changes.
- Alzheimer's disease
Alzheimer's disease is type of dementia that causes memory loss, as well as thinking and behavior problems.
- Chronic kidney disease
Chronic kidney disease is a condition of the kidneys that can cause high blood pressure, fatigue, and weakness.
- Cryptococcosis
Cryptococcosis is a lung disease causing a wide range of digestive, respiratory and cardiovascular symptoms.
- Lyme disease
Lyme disease is a bacterial infection spread through tick bites; symptoms include rash, fever chills, and more.
- Meniere's disease
Meniere's disease is a chronic inner ear condition that causes vertigo or extreme dizziness, and more.
- Stroke
A stroke occurs when blood and oxygen to the brain are cut off, and causes numbness, confusion, and more.
- Transient ischemic attack (mini-stroke)
Transient ischemic attacks cause headache, numbness, tingling, or weakness in the face, arm, or leg, and more.
- Diabetes, type 1
Diabetes can make you feel hungry, tired, or thirsty; you may urinate more than normal and have blurry vision.
- Attention deficit hyperactivity disorder (ADHD)
Attention deficit hyperactivity disorder (ADHD) makes it hard to concentrate and focus.
- High blood pressure (hypertension)
High blood pressure, often asymptomatic, can cause headaches, shortness of breath, nosebleeds, and anxiety.
- Intracranial hematoma
An intracranial hematoma occurs after a head injury and causes headache, drowsiness, confusion, and more.
- Pulmonary embolism
A pulmonary embolism, a blood clot lodged in the lung, causes shortness of breath, chest pain, and more.
- Diabetic ketoacidosis
Symptoms of diabetic ketoacidosis include dry mouth, excessive thirst and urination, and more.
- Anemia, chronic disease
Anemia of chronic disease (ACD) can cause fatigue, pale skin, weakness, dizziness, headache and more.
- Ventricular septal defect
A ventricular septal defect is a hole in the heart that some babies are born with
- Vitamin B12 deficiency
Vitamin B12 deficiency symptoms include fatigue, pale skin, weakness, sleepiness, numbness, weakness, and more.
- Thyroid storm
A thyroid storm, dangerously high levels of thyroid hormone, causes fever, racing heartbeat, sweating, and more
- Multiple sclerosis
Multiple sclerosis is a disease of the nervous system causing difficulties with balance, speech, and movement.
- Schizophrenia
Schizophrenia is a serious, chronic mental illness that causes delusional or hallucinogenic thoughts.
- Acute kidney failure
Acute kidney failure is sudden and can cause swelling, frequent dark urination, fatigue, nausea and more.
- Chemical burns
A chemical burn can cause symptoms ranging from burning and blisters to pain and shortness of breath.
- Cyanide poisoning
The symptoms of cyanide poisoning include headache, weakness, confusion, nausea, and seizures.
- Lead poisoning
Lead poisoning causes sudden pain on either side of the lower back, urinary issues, nausea, fever, and chills.
- Anemia, hemolytic
Hemolytic anemia occurs when there aren't enough red blood cells in the blood.
- Toxic shock syndrome
Toxic shock syndrome is a serious bacterial infection and causes fever, low blood pressure, a rash, and more.
- Typhoid fever
Typhoid fever is a life-threatening illness and causes fever, general aches and pains, headache, and weakness.
- West nile virus
West Nile virus is an infection spread by mosquitoes, and can cause diarrhea, fever, abdominal pain, and more.
- Small intestine cancer
Small intestine cancer is rare and often has no symptoms, but can cause symptoms in its advanced stages.
- Brain aneurysm
A brain aneurysm is a weak spot in a blood vessel in the brain that balloons and fills with blood.
- Methanol poisoning
The symptoms of methanol poisoning include trouble breathing, blindness, headache, dizziness, and more.
- Hypothyroidism (infant and child)
Hypothyroidism in children can cause delayed growth, weight gain, a puffy face, a large tongue, and more.
- Chagas disease
Chagas disease is caused by a tropical parasite and can cause fever, ill feeling, and swelling around the eye.
- Endocarditis
Signs of endocarditis, an infection of the heart, include swelling, rash, sinus congestion, nausea, and more.