Gastroenterology is the study of the gastrointestinal (GI) tract of the body. A gastroenterologist diagnoses and treats diseases of the digestive organs, including the stomach, esophagus, intestines, pancreas, liver and gallbladder. This specialist treats conditions such as abdominal pain, nausea and vomiting, ulcers, diarrhea, cancer in the GI tract, and jaundice. A gastroenterologist also performs complex diagnostic procedures, including the use of endoscopes to see and treat internal organs.

Physicians in this specialty treat patients suffering from numerous diseases and illnesses, but some of the most common are Hemorrhoids, Hiatal Hernia, Digestive Disorders, heartburn, Rectal Bleeding, Ulcer, Ostomy Care, Polyps, colon cancer, Crohn's Disease, Diarrhea, Abdominal Pain, Constipation, acid reflux, Bowel Diseases, cystic fibrosis, Ulcerative Colitis, Nausea, Appendicitis, and Colitis.

Once properly diagnosed, practitioners can perform numerous procedures on patients including GERD Services, abdominal surgery, Appendectomy, Cholecystectomy, laparoscopy, Liver Transplantation, and Cholecystography.

To diagnose patients with possible illnesses and diseases, specialists will often perform one of many tests including endoscopy, Colonoscopy, Barium Enema, Liver Biopsy, Sigmoidoscopy, Barium Swallow, Abdominal Ultrasound, Esophagogastroduodenoscopy (EGD), Gallbladder Scan, Upper Gastrointestinal Series, Endoscopic Retrograde Cholangiopancreatography, Radiographic X-Ray, Proctoscopy, Pancreas Scan, Abdominal Angiogram, Anoscopy, Liver Scan, and Abdominal X-rays.

Doctor density varies by specialty and location. California has 1,619 practicing gastroenterologists. Broken out by city, gastroenterology doctor density in Agoura Hills is 4, in Alameda is 6, in Anaheim is 33, in Apple Valley is 5, in Arcadia is 13, in Bakersfield is 17, in Baldwin Park is 10, in Berkeley is 17, in Beverly Hills is 18, in Brea is 4, in Burbank is 18, in Burlingame is 5, in Chula Vista is 9, in Concord is 12, in Corona is 7, in Culver City is 9, in Daly City is 6, in Duarte is 4, in El Cajon is 4, in Encinitas is 5, in Escondido is 4, in Eureka is 3, in Fairfield is 4, in Fountain Valley is 12, in Fremont is 13, in Fresno is 35, in Fullerton is 9, in Garden Grove is 11, in Gilroy is 2, in Glendale is 19, in Hemet is 6, in Highland is 7, in Huntington Beach is 12, in Irvine is 26, in La Mesa is 12, in Laguna Beach is 3, in Laguna Hills is 10, in Lancaster is 17, in Livermore is 9, in Loma Linda is 26, in Long Beach is 32, in Los Alamitos is 12, in Los Angeles is 207, in Los Gatos is 3, in Manhattan Beach is 3, in Menlo Park is 2, in Merced is 4, in Mission Viejo is 18, in Modesto is 12, in Montebello is 5, in Monterey is 11, in Monterey Park is 15, in Mountain View is 14, in Murrieta is 11, in Napa is 4, in National City is 5, in Needles is 1, in Newport Beach is 23, in Novato is 3, in Oakland is 22, in Oceanside is 7, in Orange is 48, in Palm Springs is 8, in Palo Alto is 59, in Pasadena is 20, in Petaluma is 2, in Placentia is 5, in Pleasanton is 5, in Pomona is 6, in Poway is 9, in Rancho Mirage is 10, in Redondo Beach is 1, in Redwood City is 9, in Ridgecrest is 3, in Riverside is 17, in Roseville is 15, in Sacramento is 58, in San Clemente is 7, in San Diego is 113, in San Francisco is 100, in San Jose is 46, in San Luis Obispo is 7, in San Mateo is 7, in San Ramon is 9, in Santa Barbara is 11, in Santa Cruz is 10, in Santa Maria is 6, in Santa Monica is 27, in Santa Rosa is 18, in Simi Valley is 8, in Stockton is 8, in Sunnyvale is 7, in Thousand Oaks is 12, in Torrance is 36, in Upland is 9, in Vacaville is 4, in Visalia is 4, in Walnut Creek is 26, in Whittier is 9, and in Yorba Linda is 2.

California’s population is 36,142,137, and it is America’s third largest and most populous state. It also claims the highest and lowest altitudes in the lower 48 states. The lowest point in the country, Death Valley, is also home to the nation’s highest recorded temperature, 134 degrees. Tourists flock to this state for its many outdoor activities and attractions, including Universal Studios, Disneyland, Rodeo Drive shopping, the Golden Gate Bridge in San Francisco, wine country tours, and California’s numerous beaches and parks. Los Angeles is the nation’s second largest city, but California’s capital is Sacramento. The giant sequoias in California’s forests are among the oldest living things in the world, and a redwood in the Redwood National Park is said to be the world’s tallest tree, at 365 feet. California achieved statehood in 1850, and was named the Golden State after the beginning of the Gold Rush in 1848.

According to 2005 Census estimates, California has a population of 36,132,147. Of this population, 9,308,563 are under the age of 18 and 3,827,038 are at or above the age of 65.