Complications of oral contraceptives (OCs) affecting the gastrointestinal tract, liver and pancreas are rare but potentially serious. Hepatobiliary complications are by far the most frequent and varied. Hepatic lesions will probably decline in frequency as low-dose OCs replace higher dosed pills. Intrahepatic cholestasis induced by OCs resembles that of pregnancy. There may be a genetic predisposition to both conditions involving a dose-dependent estrogen effect of decreasing bile secretion. Intrahepatic cholestasis appears within 6 cycles of OC use. Symptoms include pruritus with anorexia, asthenia, vomiting, and weight loss without fever, rash or abdominal pain. Termination of OCs clears the condition without sequelae within 1-3 months, sometimes after a temporary aggravation. A moderate and asymptomatic cytolysis may appear when OC treatment is begun. Sinusoidal dilatation has been conclusively linked to OCs although few cases have been published. Clinical manifestations other than hepatomegaly are variable. Abdominal pain and fever are the most common. The condition is not related to duration of use and disappears 5-15 days after OC use is terminated. The relative risk of Budd-Chiari syndrome in OC users is estimated at 2.37. OCs increase the prevalence of hepatic adenomas as a function of duration of treatment. They are usually discovered fortuitously but may be revealed by vague abdominal pains. Hemorrhagic complications are more likely in OC users. It may be difficult to distinguish between adenomas, hepatocellular carcinoma, and focal nodular hyperplasia. A puncture biopsy guided by sonography may aid diagnosis. The natural history of adenomas is poorly understood and treatment remains controversial. OCs do not appear to increase the risk of focal nodular hyperplasia but they increase the size of the tumor and the risk of hemorrhage. OCs should be terminated because of risk of hemorrhage. Surgical resection is not indicated unless there are complication or diagnostic doubts. While hepatocellular carcinoma is very rare, its risk is increased by a factor of 7-20 in women using OCs for 8 years or more. Use of combined OCs appears to speed development of lithiasis in predisposed women. Risk of lithiasis is linked to estrogen content in women under 30. Several cases of acute pancreatitis in the 1st 3 months of treatment have been reported in women with preexisting lipid metabolic anomalies. Cases of ischemic lesions of the small intestine or colon have been reported in OC users with A positive blood type. Such lesions can be fatal without early diagnosis and termination of OCs. Gastric esophageal reflux is increased by progestins. Preexisting constipation may be aggravated and the incidence of Crohn's disease increased by OCs. It is advisable to rule out preexisting hepatic pathology before prescribing OCs. OCs should be stopped in case of viral hepatitis.