- Medication reaction or side-effect
Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more.
- Sleep apnea
People with sleep apnea stop and restart breathing multiple times while sleeping.
- Sleep deprivation
Sleep deprivation occurs when the lack of restful sleep is severe enough to compromise basic body functions.
- Dementia with Lewy bodies
Dementia with Lewy bodies is a brain disorder that causes problems managing memory and movement.
- Schizophrenia
Schizophrenia is a serious, chronic mental illness that causes delusional or hallucinogenic thoughts.
- Low blood sugar (hypoglycemia)
Low blood sugar, or low glucose levels, causes shakiness, anxiety, clammy skin, irritability, hunger, and more.
- Bipolar disorder
Bipolar disorder causes extreme mood swings between depression and mania.
- Narcolepsy
Narcolepsy is a brain disorder that makes people abnormally sleepy at times during the day.
- Insomnia
Insomnia symptoms include trouble staying asleep at night, feeling tired during the day, moodiness, and more.
- Aspirin poisoning
Aspirin poisoning is a medical emergency and can cause nausea, vomiting, drowsiness and more.
- Hypothyroidism (adult)
Hypothyroidism your body functions slow down, making you gain weight and feel tired all the time.
- Head injury
Symptoms of a head injury vary but include headache, nausea, dizziness, memory problems, confusion, and more.
- Alcohol withdrawal (delirium tremens)
Alcohol withdrawal causes anxiety, depression, headaches, nightmares, fatigue, sweating, and shakiness.
- Generalized anxiety disorder
Generalized anxiety disorder is a condition in which a person has nearly constant anxiety.
- Dehydration (Children)
Dehydration, or not getting enough fluid, causes dry and sticky mouth, tearless crying, and more in children.
- Caffeine withdrawal
If you suddenly stop drinking caffeine, you get withdrawal symptoms, such as headache, fatigue, and bad mood.
- Postconcussive syndrome
Postconcussive syndrome occurs when the symptoms of a concussion or other brain injury continue to occur.
- Depression (Adult)
Depression is a painful sadness that interferes with daily life and includes hopelessness, anxiety, and more.
- Encephalitis
Encephalitis is swelling and inflammation of the brain from an infection causing sleepiness, fever, and more.
- Intracranial hematoma
An intracranial hematoma occurs after a head injury and causes headache, drowsiness, confusion, and more.
- Lyme disease
Lyme disease is a bacterial infection spread through tick bites; symptoms include rash, fever chills, and more.
- Stroke
A stroke occurs when blood and oxygen to the brain are cut off, and causes numbness, confusion, and more.
- Multiple sclerosis
Multiple sclerosis is a disease of the nervous system causing difficulties with balance, speech, and movement.
- Cocaine abuse
Cocaine abuse occurs when a person continues using it despite the social and health problems caused by it.
- Depression (Child and Adolescent)
Depression is a painful sadness that interferes with a child's schoolwork, family life, and social activities.
- Diabetic ketoacidosis
Symptoms of diabetic ketoacidosis include dry mouth, excessive thirst and urination, and more.
- Drug overdose
A drug overdose can be fatal and causes sleepiness, confusion, coma, vomiting, and other symptoms.
- Insulin reaction (hypoglycemia)
An insulin reaction is the result of low blood sugar and causes anxiety, hunger, shaking, dizziness, and more.
- Barbiturate abuse
Barbiturates are a type of prescription sedative in which even a slight overdose can cause coma or death.
- 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.
- Atrial fibrillation
Atrial fibrillation is a heart condition that causes heart palpitations, confusion, dizziness and more.
- Anemia, iron deficiency
Anemia , a lack of red blood cells, can cause fatigue, pale skin and gums, brittle nails, irritability, and more.
- Restless legs syndrome
Restless leg syndrome causes intense discomfort in your legs and an overpowering urge to move them.
- Porphyria
Porphyria is a condition that can affect the nerves and skin, making the skin extremely sensitive to sunlight.
- Post-traumatic stress disorder (PTSD)
Post-traumatic stress disorder (PTSD) can cause tension, depression, and other symptoms of anxiety.
- Thyroid storm
A thyroid storm, dangerously high levels of thyroid hormone, causes fever, racing heartbeat, sweating, and more
- Vitamin B12 deficiency
Vitamin B12 deficiency symptoms include fatigue, pale skin, weakness, sleepiness, numbness, weakness, and more.
- 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.
- Epilepsy (temporal lobe)
Epilepsy is a condition marked by seizures.
- Epilepsy (simple partial seizures)
During simple partial epileptic seizures, people remain fully conscious, able to respond to external stimuli.
- Epilepsy (complex partial seizures)
During complex partial seizures, people lose consciousness briefly.
- Puberty
Puberty is the time when a young person becomes sexually mature.
- Methamphetamine use
Methamphetamine use causes increased blood pressure, rapid heart rate, enlarged pupils, sweating, and more.
- Grief reaction
Grief reaction, the way someone copes with a loss, causes include anger, sadness, anxiety, guilt, and more.
- Intoxication
Symptoms of intoxication include euphoria, slowed reaction time, dizziness, confusion, numbness, and more.
- Nicotine withdrawal/cessation of smoking
Symptoms of nicotine withdrawal include a craving for cigarettes, headaches, bad mood, anxiety, and more.
- Benzodiazepine abuse
Benzodiazepines are prescription medications that cause drowsiness, dizziness, blurred vision, and more.
- 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.
- Dehydration (Adult)
Dehydration, or not getting enough fluid, causes low blood pressure, weakness, dizziness, fatigue, and nausea.
- 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.
- Transient global amnesia
Transient global amnesia is a sudden loss of memory. Symptoms usually last for hours and then memory returns.
- Dementia in head injury
Dementia resulting from a head injury may cause memory problems, difficulty speaking, and personality changes.
- Acute kidney failure
Acute kidney failure is sudden and can cause swelling, frequent dark urination, fatigue, nausea and more.
- Hypothyroidism (infant and child)
Hypothyroidism in children can cause delayed growth, weight gain, a puffy face, a large tongue, and more.
- Nitrogen narcosis
Nitrogen narcosis is caused by breathing compressed air causing coordination issues, lightheadedness, and more.
- Methanol poisoning
The symptoms of methanol poisoning include trouble breathing, blindness, headache, dizziness, and more.
- Chagas disease
Chagas disease is caused by a tropical parasite and can cause fever, ill feeling, and swelling around the eye.
- Pellagra
Pellagra is a late stage of vitamin B3 deficiency; it causes dermatitis, diarrhea, dementia, and death.
- Toxic shock syndrome
Toxic shock syndrome is a serious bacterial infection and causes fever, low blood pressure, a rash, and more.
- Anemia, hemolytic
Hemolytic anemia occurs when there aren't enough red blood cells in the blood.
- Brain tumor
Primary brain tumors are often benign but can cause seizures, ongoing headaches, or loss of coordination.
- Brain infection
A brain infection is inflammation of the brain or spinal cord and can cause nausea, fever, seizures and more.
- Lead poisoning
Lead poisoning causes sudden pain on either side of the lower back, urinary issues, nausea, fever, and chills.
- Cyanide poisoning
The symptoms of cyanide poisoning include headache, weakness, confusion, nausea, and seizures.
- 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.
- Endocarditis
Signs of endocarditis, an infection of the heart, include swelling, rash, sinus congestion, nausea, and more.
