In-depth

Abdominal aortic aneurysm

Acute liver failure

Addison's disease

Alcoholic hepatitis

Alcoholic liver disease

Anaphylaxis

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

Antibiotic-associated diarrhea

Aortic aneurysm

Appendicitis

Ascariasis

Barrett's esophagus

Behcet's disease

Bile reflux

Bladder stones

Blastocystis hominis infection

Blind loop syndrome

Botulism

C. difficile infection

Carcinoid tumors

Cardiogenic shock

Celiac disease

Chagas disease

Chlamydia

Are you worried you might have chlamydia? Find out how this common sexually transmitted infection is diagnosed and treated.

Cholecystitis

Chronic lymphocytic leukemia

Churg-strauss syndrome

Colon cancer

Colon polyps

Constipation in children

Crohn's disease

Cyclic vomiting syndrome

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

Dengue fever

Diabetic ketoacidosis

Diabetic neuropathy

Diarrhea

Diverticulitis

E. coli

Ectopic pregnancy

Egg allergy

Encopresis

Enlarged liver

Enlarged spleen (splenomegaly)

Eosinophilic esophagitis

Epididymitis

Esophagitis

Fibromuscular dysplasia

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

Gallstones

Gallstones often don't cause symptoms. But if you have a gallbladder attack, you're not likely to forget it.

Gallstones

Gas and gas pains

Intestinal gas can be embarrassing and sometimes painful. But a few simple measures can often provide relief.

Giardiasis

Gonorrhea

H. pylori infection

Hantavirus pulmonary syndrome

Headaches in children

Heart attack

Hemolytic uremic syndrome (HUS)

Henoch-Schonlein purpura

Hepatitis A

Hepatitis B

Hives and angioedema

Hypercalcemia

Hyperglycemia in diabetes

Inflammatory bowel disease (IBD)

Intestinal ischemia

Intestinal obstruction

Irritable bowel syndrome

Ischemic colitis

Kawasaki disease

Kidney infection

Lactose intolerance

Lead poisoning

Liver cancer

Liver disease

Liver hemangioma

Mental illness

Mesenteric lymphadenitis

Mesothelioma

Milk allergy

Miscarriage

Mittelschmerz

Neuroblastoma

Non-Hodgkin's lymphoma

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.

Ovarian hyperstimulation syndrome

Pancreatic cancer

Pancreatic cysts

Pancreatitis

Pelvic inflammatory disease (PID)

Peritonitis

Pheochromocytoma

Pinworm infection

Placental abruption

Plague

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

Primary biliary cirrhosis

Primary sclerosing cholangitis

Proctitis

Pseudomembranous colitis

Rotavirus

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.

Scrotal masses

Sexually transmitted diseases

Shellfish allergy

Shigella infection

Small vessel disease

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

Toxic hepatitis

Traveler's diarrhea

Trichinosis

Triple X syndrome

Typhoid fever

Ulcerative colitis

Vasculitis

Vesicoureteral reflux

Whipple's disease

Wilms' tumor

Yellow fever

Zollinger-Ellison syndrome

Oct. 25, 2016