In-depth

Acute kidney failure

Acute liver failure

Agoraphobia

Do you feel trapped in your own home? Do you worry about having a panic attack? Find out how agoraphobia can be treated.

Alcohol intolerance

Alcohol use disorder

Allergies

Amniotic fluid embolism

Anaphylaxis

Anaphylaxis is the most serious type of allergic reaction. It often occurs rapidly after exposure to an allergen and may be life-threatening.

Angina

Anthrax

Antibiotic-associated diarrhea

Antibiotics save lives, but they can also have side effects. The most common are mild to severe diarrhea and a serious type of colitis.

Appendicitis

Ascariasis

Bee stings

Bee stings — Comprehensive overview covers prevention, treatment of bee stings.

Benign paroxysmal positional vertigo (BPPV)

Bile reflux

Bird flu (avian influenza)

Blind loop syndrome

Botulism

Brain aneurysm

Carbon monoxide poisoning

Cardiogenic shock

Castleman disease

Celiac disease

Celiac disease is an immune reaction to gluten, a protein found in certain foods. As a result, the body is unable to absorb some important nutrients.

Chagas disease

Chest pain

Cholecystitis

Cholera

Cholera causes severe diarrhea and can kill in a matter of hours, yet can be easily treated with oral or intravenous fluids.

Chronic daily headaches

Churg-Strauss syndrome

Churg-Strauss syndrome is a rare disorder marked by blood vessel inflammation that affects organs throughout the body. Asthma is the most common sign.

Colon polyps

Concussion

Concussions can be serious injuries that need sufficient time to heal.

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia is a genetic condition affecting the adrenal glands and interfering with normal growth and development in boys and girls.

Constipation in children

Constipation in children is common. Often, simple changes in diet and routine are helpful.

Cryptosporidium infection

Cryptosporidium infection may cause diarrhea in healthy people, but for people with HIV/AIDS and weakened immune systems, the illness can cause serious complications.

Cyclic vomiting syndrome

Cyclic vomiting syndrome can last for hours or days and shares many triggers with migraines.

Cyclospora infection

Dengue fever

Diabetic coma

Diabetic ketoacidosis

Diabetic neuropathy

Diverticulitis

Drug allergy

Dumping syndrome

Dysphagia

E. coli

Ebola virus and Marburg virus

Ectopic pregnancy

Egg allergy

Ehrlichiosis

Encephalitis

Encephalitis is inflammation of the brain usually caused by a viral infection. Severe cases can cause brain damage, even death.

Endometriosis

Endometriosis is a common and often painful disorder in which tissue that normally lines the inside of your uterus grows outside your uterus.

Enlarged liver

Eosinophilic esophagitis

Esophagitis

Exercise headaches

Food allergy

Food allergy symptoms can make you miserable. Unfortunately, there's no cure — but there are steps you can take to keep your symptoms in check.

Food poisoning

Food poisoning has many forms, and some can be serious. Here's how to recognize food poisoning and ways to prevent getting sick.

Gallbladder cancer

Gastritis

Gastroparesis

Giardiasis

Glaucoma

H. pylori infection

Hangovers

Hantavirus pulmonary syndrome

Hantavirus pulmonary syndrome is initiated by a rodent-carried virus that infects the lung tissues, bringing on flu-like symptoms, respiratory problems and even death.

Heart attack

Heart failure

Heat exhaustion

Heatstroke

Hemophilia

Henoch-Schonlein purpura

Henoch-Schonlein purpura causes inflammation of small blood vessels (vasculitis) and often a purplish rash. It's most common in children ages 2 to 6.

Hepatitis A

Hepatitis B

Hydrocele

Hypercalcemia

Hyperglycemia in diabetes

Hyponatremia

Indigestion

Indigestion can ruin meals and make you feel uncomfortable. Take steps to prevent symptoms like upset stomach, bloating and pain.

Intestinal ischemia

Intracranial hematoma

Jellyfish stings

Kawasaki disease

Kawasaki disease — the leading cause of acquired coronary disease in children — causes artery wall inflammation throughout the body. It affects children younger than age 5.

Kidney stones

Krabbe disease

Krabbe disease is a rare, inherited disorder — most often affecting infants — that impairs functioning of the central nervous system and usually leads to early death.

Lactose intolerance

Lead poisoning

Legionnaires' disease

Legionnaires' disease, a severe form of pneumonia, is caused by bacteria that can live in water in air conditioning systems, showers and spas.

Listeria infection

Most people exposed to listeria don't become ill. But for those at risk of a listeria infection — a foodborne illness — the consequences can be severe.

Liver disease

Liver hemangioma

Liver hemangioma is the most common type of noncancerous (benign) liver mass. Learn how doctors treat liver hemangioma.

Low blood pressure (hypotension)

Low blood pressure (hypotension) can be a sign of good health or of a life-threatening condition. Find out more about hypotension's causes and treatment options.

Menstrual cramps

A monthly period is bad enough. Add in painful menstrual cramps, and you may be cursing this thing called womanhood. How do you get relief?

Mesenteric lymphadenitis

Mesenteric lymphadenitis is an inflammation of the lymph nodes in the tissue that attaches various organs to your abdominal wall (mesentery). It mainly affects children.

Milk allergy

Molar pregnancy

Morning sickness

Multiple myeloma

Myocardial ischemia

Naegleria infection

Nonulcer stomach pain

Norovirus infection

Noroviruses cause an intestinal flu-like illness that typically resolves within days. Norovirus infection is highly contagious, especially in closed settings like hospitals and cruise ships.

Orchitis

Orthostatic hypotension (postural hypotension)

Orthostatic hypotension (postural hypotension) is a form of low blood pressure that occurs when you stand up.

Ovarian cancer

Ovarian cysts

Ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) — Comprehensive overview covers symptoms, treatment of this complication of infertility treatment.

Pancreatic cysts

Pancreatitis

The pain of pancreatitis, an inflammation of the pancreas, can last for days, or in chronic cases, for years. Pancreatitis can lead to serious complications.

Panic attacks and panic disorder

Parvovirus infection

Peanut allergy

Pelvic inflammatory disease (PID)

Peptic ulcer

Peptic ulcers are painful sores that commonly affect the lining of your stomach and upper small intestine. The most frequent cause is a treatable infection.

Peritonitis

Pinworm infection

Polio

One of the most feared diseases of the 20th century, polio has been eradicated from the developed world but remains a threat in less developed nations.

Polymorphous light eruption

Polymorphous light eruption is a sun-induced skin rash affecting people who develop a sensitivity to sunlight.

Porphyria

Porphyria is a group of inherited disorders that result from buildup of natural chemicals call porphyrins, which can cause nervous system and skin problems.

Postpartum preeclampsia

Preeclampsia

Pseudotumor cerebri

Pseudotumor cerebri — Comprehensive overview covers symptoms, causes, treatment of increased pressure inside the skull.

Q fever

Radiation sickness

Recurrent breast cancer

Reye's syndrome

Rocky Mountain spotted fever

Ruptured eardrum

A ruptured eardrum causes hearing loss and can give bacteria easy access to your middle ear. A ruptured eardrum usually heals without treatment.

Salmonella infection

Salmonella infection will cause only diarrhea and stomach pain in some people, but for infants and immunocompromised people, this bacterial illness can cause life-threatening complications.

Scarlet fever

Scarlet fever is a bacterial infection that causes a rash, fever and sore throat and usually affects children and adolescents.

Scrotal masses

Shaken baby syndrome


Shellfish allergy

Smallpox

Social anxiety disorder

Spinal headaches

Spontaneous coronary artery dissection (SCAD)

Find out about this rare cause of heart attack in young, healthy people.

Staph infections

Swine flu (H1N1 flu)

Symptom Checker

Foot pain? Headache? Sore throat? Skin rash? Use the Symptom Checker to find out what's causing your symptom.

Tapeworm infection

Testicular torsion

Thunderclap headaches

Toxic hepatitis

Toxic hepatitis is liver damage that occurs when your liver isn't able to break down certain toxins — including common pain relievers such as Tylenol.

Toxic shock syndrome

Traumatic brain injury

While mild traumatic brain injury generally results in few long-term problems, more severe injury can cause several physical, emotional, behavioral, communication and cognitive problems.

Traveler's diarrhea

Traveler's diarrhea is unpleasant. Find out how to avoid this travel-related health problem.

Tularemia

Ventricular fibrillation

Wheat allergy

Whooping cough

Wilson's disease

Yellow fever

Zollinger-Ellison syndrome

Sept. 04, 2014