Gastroenteritis Gastroenteritis is inflammation of the stomach and intestine that causes diarrhea and vomiting. Irritable bowel syndrome Irritable bowel syndrome is a common condition that causes painful spasms and cramping in the large intestine. Food poisoning Food poisoning can cause abdominal pain, diarrhea, nausea, vomiting, fever, chills, and weakness. Lactose intolerance Lactose intolerance, or the inability to digest lactose, leads to gas, bloating, and other symptoms. Traveler s diarrhea Traveler s diarrhea causes watery diarrhea and cramps, sometimes with a low-grade fever. Drug overdose A drug overdose can be fatal and causes sleepiness, confusion, coma, vomiting, and other symptoms. Viral gastroenteritis Gastroenteritis (stomach flu) is a viral condition that causes diarrhea and vomiting. Medication reaction or side-effect Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more. Iron poisoning Iron poisoning causes abdominal pain, vomiting, diarrhea, lethargy, and dehydration. Giardiasis Giardiasis is an infection of the small intestine causing diarrhea, gas, bloating, nausea and stomach cramps. Sickle cell disease Sickle cell disease symptoms include repeated infections, yellow skin, fatigue, dizziness, pain, and more. Diabetic ketoacidosis Symptoms of diabetic ketoacidosis include dry mouth, excessive thirst and urination, and more. Constipation (child) Constipation is having less than three bowel movements a week, causing hard stools, abdominal pain and more. Constipation (adult) Constipation is having less than three bowel movements a week, causing hard stools, abdominal pain and more. Campylobacter Campylobacter is an intestinal infection causing abdominal pain and cramping, nausea, diarrhea, and vomiting. Panic attack When someone has a panic attack, that person feels a sudden, intense fear that can t be controlled. Peptic ulcer Peptic ulcers, sores in the lining of the stomach or upper intestine, cause abdominal pain, gas, and more. Gastritis Gastritis is an inflammation of the stomach lining, causes stomach upset, irritation, and pain. Generalized anxiety disorder Generalized anxiety disorder is a condition in which a person has nearly constant anxiety. Antibiotic use Antibiotics can cause stomach pain, diarrhea, nausea, vomiting, itching, rashes and dizziness. Inflammatory bowel disease Inflammatory bowel disease causes swelling and symptoms such as cramping, chronic diarrhea, and bleeding. Helicobacter pylori infection Helicobacter, bacteria in the digestive tract, causes peptic ulcers and their associated pain and burning. Hyperthyroidism Hyperparathyroidism can cause fatigue and weakness, increased thirst, impaired thinking, and bone fractures. Acute kidney failure Acute kidney failure is sudden and can cause swelling, frequent dark urination, fatigue, nausea and more. Low blood sugar (hypoglycemia) Low blood sugar, or low glucose levels, causes shakiness, anxiety, clammy skin, irritability, hunger, and more. Polycystic kidney disease Polycystic kidney disease can cause abdominal pain, headaches, and pain in the sides and back. Porphyria Porphyria is a condition that can affect the nerves and skin, making the skin extremely sensitive to sunlight. Carbon monoxide poisoning Carbon monoxide poisoning can be fatal, symptoms include headache, dizziness, nausea, and vomiting. Chronic kidney disease Chronic kidney disease is a condition of the kidneys that can cause high blood pressure, fatigue, and weakness. Swallowed object Symptoms of swallowing an object include coughing, choking, vomiting, throat pain, breathing trouble, and more. Pyloric stenosis Pyloric stenosis, a condition that affects infants, causes vomiting after eating, constant hunger, and more. Motion sickness Motion sickness is a feeling of queasiness or nausea caused by moving in a car, bus, boat, or plane. Intestinal Ileus Intestinal ileus is a condition of the intestinal muscles causing cramps and bloating, vomiting, gas, and more. Pancreatic cancer Pancreatic cancer is typically asymptomatic until the cancer has advanced, making treatment difficult. Drug allergy A drug allergy is an allergic reaction to a medication and can cause a rapid heartbeat and difficulty breathing. Drug dependence and abuse Symptoms of drug dependence and abuse include bloodshot eyes, frequent nosebleeds, drowsiness, and more. Esophagitis Esophagitis, an inflammation of the lining of the esophagus, causes chest pain, nausea, and more. Labyrinthitis Labyrinthitis, an infection and swelling in the inner ear, and may cause vertigo or hearing loss. Narcotic abuse Narcotic abuse can cause fatigue, shallow breathing, anxiety, euphoria, vomiting, confusion, and constipation. Glaucoma Glaucoma is a group of eye conditions in which fluid builds up in your eye causing gradual vision loss. Heat exhaustion Heat exhaustion causes intense thirst, heavy sweating, pale, cool, and moist skin, muscle cramps, and more. Antibiotic-associated diarrhea Antibiotic-associated diarrhea is frequent, watery bowel movements that happen after taking antibiotics. Celiac disease Celiac disease, which is an intestinal reaction to gluten, can cause gas, diarrhea, bloating, and weight loss. Colon cancer Colon cancer is often asymptomatic, but it can cause constipation, bowel obstruction, bloody stool and more. Crohn s disease Crohn s disease is a digestive condition that causes swelling, cramping, diarrhea, and nutritional problems. Cystic fibrosis Cystic fibrosis is an inherited disease that causes the body to produce abnormally thick and sticky mucus. Gallstones A gallstone attack occurs when a stone blocks the bile duct, causes right upper abdominal pain and cramping. Hepatitis A Hepatitis A is an inflammation of the liver. Symptoms include fever, fatigue, yellowing of the skin, and more. Hepatitis B Hepatitis B is an inflammation of the liver that may cause fever, fatigue, dark urine, jaundice, and more. Intestinal obstruction Intestinal obstruction is when the intestine is blocked and causes pain, swelling, nausea, diarrhea, and more. Intracranial hematoma An intracranial hematoma occurs after a head injury and causes headache, drowsiness, confusion, and more. Rotavirus Rotavirus is an inflammation of the stomach and intestines leading to diarrhea and vomiting. Salmonella Salmonella are a type of bacteria that can infect the body and cause diarrhea, cramps, and fever. Shigellosis Shigellosis is irritation of the stomach and intestine and causes bloody diarrhea, abdominal pain, and fever. Stool holding (encopresis) Young children with encopresis soil their underwear or clothing with unintentional bowel movements. Stroke A stroke occurs when blood and oxygen to the brain are cut off, and causes numbness, confusion, and more. Mumps Mumps is a contagious viral disease that causes painful swelling of the glands that produce saliva. Ulcerative colitis Ulcerative colitis causes swelling in the large intestine and can lead to cramping, diarrhea, and more. Diverticulosis Diverticulosis is a condition of the colon and causes pain, cramping, infection, bleeding, and other symptoms. Botulinum toxin (Botox) injection Botulinum toxin side effects may include pain and tenderness at the injection site, headache, nausea and more. Amebiasis Amebiasis is an intestinal parasitic infection causing diarrhea, cramps, gas, fever, and fatigue. Allergic reaction Allergic reaction causes sneezing, runny nose and hives and can lead to anaphylaxis, a whole body reaction. Hyperparathyroidism Hyperthyroidism causes weight loss, shakiness, tiredness, sensitivity to heat, insomnia, and more. Tick bite A tick-related illness may cause a rash that expands out from the site of the bite, fever, chills, and more. Ricin poisoning Ricin is a dangerous poison in castor beans, and causes trouble breathing, nausea, fever and sweating. Toxic shock syndrome Toxic shock syndrome is a serious bacterial infection and causes fever, low blood pressure, a rash, and more. Mesenteric lymphadenitis Mesenteric lymphadenitis is an inflammation of abdominal lymph nodes causing pain, diarrhea, fever, and more. Henoch-schonlein purpura Henoch-Sch�nlein purpura is a condition that causes a purple bruise-like rash on the legs and buttocks. Small intestine cancer Small intestine cancer is rare and often has no symptoms, but can cause symptoms in its advanced stages. Typhoid fever Typhoid fever is a life-threatening illness and causes fever, general aches and pains, headache, and weakness. Brain aneurysm A brain aneurysm is a weak spot in a blood vessel in the brain that balloons and fills with blood. Radiation sickness Radiation sickness is caused by a high dose of radiation, and causes vomiting, diarrhea, hair loss, and more. Lead poisoning Lead poisoning causes sudden pain on either side of the lower back, urinary issues, nausea, fever, and chills. Hypopituitarism Hypopituitarism is a rare disorder of the pituitary glands, which can cause many different symptoms. 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. Stomach cancer Early stomach cancer may cause commonly misdiagnosed symptoms such as indigestion, nausea, and poor appetite. Cholera Cholera is a bacterial infection that can cause diarrhea, nausea, excessive thirst, dry skin and vomiting. Budd-Chiari syndrome Budd-Chiari syndrome is a rare liver condition, symptoms include pain, swelling, and vomiting blood. Carcinoid syndrome Carcinoid syndrome is a group of symptoms such as flushing, wheezing, and diarrhea that may develop in people who have carcinoid cancer.