- Sleep apnea
People with sleep apnea stop and restart breathing multiple times while sleeping.
- Medication reaction or side-effect
Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more.
- Narcolepsy
Narcolepsy is a brain disorder that makes people abnormally sleepy at times during the day.
- Heart rhythm disorder
Some heart rhythm disorders can cause a fluttering in the chest, shortness of breath, chest pain or dizziness.
- Generalized anxiety disorder
Generalized anxiety disorder is a condition in which a person has nearly constant anxiety.
- Sleep deprivation
Sleep deprivation occurs when the lack of restful sleep is severe enough to compromise basic body functions.
- Caffeine withdrawal
If you suddenly stop drinking caffeine, you get withdrawal symptoms, such as headache, fatigue, and bad mood.
- Fainting (vasovagal syncope)
Before fainting, you might feel lightheaded, warm, nausea, a cold sweat, or have tunnel vision.
- Supraventricular tachycardia
Supraventricular tachycardia is fast heart rhythm starting in one of the upper chambers of the heart.
- Hyperventilation
Hyperventilation is rapid or shallow breathing usually caused by stress or anxiety.
- Atrial fibrillation
Atrial fibrillation is a heart condition that causes heart palpitations, confusion, dizziness and more.
- Insomnia
Insomnia symptoms include trouble staying asleep at night, feeling tired during the day, moodiness, and more.
- Restless legs syndrome
Restless leg syndrome causes intense discomfort in your legs and an overpowering urge to move them.
- High blood pressure (hypertension)
High blood pressure, often asymptomatic, can cause headaches, shortness of breath, nosebleeds, and anxiety.
- Low blood pressure (hypotension)
Low blood pressure, or hypotension, can make you feel lightheaded and dizzy
- 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.
- Atrial flutter
Atrial flutter is an abnormality of the heart's rhythm that causes rapid and sometimes irregular heartbeats.
- Aspirin poisoning
Aspirin poisoning is a medical emergency and can cause nausea, vomiting, drowsiness and more.
- Acute kidney failure
Acute kidney failure is sudden and can cause swelling, frequent dark urination, fatigue, nausea and more.
- Anemia
Anemia, a lack of red blood cells, can cause fatigue, pale skin, weakness, dizziness, headache and more.
- Anemia, chronic disease
Anemia of chronic disease (ACD) can cause fatigue, pale skin, weakness, dizziness, headache and more.
- Labyrinthitis
Labyrinthitis, an infection and swelling in the inner ear, and may cause vertigo or hearing loss.
- Thalassemia
Thalassemia is a rare group of genetic blood disorders effecting red blood cells and leading to anemia.
- Aortic regurgitation
Aortic regurgitation, when the aortic valve doesn't close completely, can cause severe heart symptoms.
- Cocaine withdrawal
Cocaine withdrawal may cause feelings ranging from anxiety, irritability and sleepiness to suicidal thoughts.
- Amphetamine withdrawal
The symptoms of amphetamine withdrawal include depression, fatigue, increased appetite, and sleep problems.
- Anemia, iron deficiency
Anemia , a lack of red blood cells, can cause fatigue, pale skin and gums, brittle nails, irritability, and more.
- 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.
