What causes esophageal varices

Content on WhatAnswers is provided "as is" for informational purposes. While we strive for accuracy, we make no guarantees. Content is AI-assisted and should not be used as professional advice.

Last updated: April 4, 2026

Quick Answer: Esophageal varices are enlarged veins in the lower part of the esophagus, most commonly caused by portal hypertension, a condition where blood pressure in the portal vein system (which carries blood from the digestive organs to the liver) becomes abnormally high. This elevated pressure forces blood to back up into smaller veins, like those in the esophagus, causing them to swell.

Key Facts

Portal hypertension is the primary cause of esophageal varices in over 90% of cases.
Liver cirrhosis, particularly due to chronic alcohol abuse or viral hepatitis (B and C), is the leading cause of portal hypertension.
Other causes of portal hypertension include blood clots in the portal vein, schistosomiasis, and certain rare congenital conditions.
Esophageal varices do not typically cause symptoms until they bleed, which is a life-threatening emergency.
The risk of bleeding from esophageal varices increases with their size and the severity of liver disease.

What are Esophageal Varices?

Esophageal varices are abnormally swollen veins that develop in the lower part of the esophagus. The esophagus is the tube that connects the throat to the stomach. These swollen veins are often a serious complication of liver disease, particularly cirrhosis. While they may not cause symptoms on their own, they carry a significant risk of bleeding, which can be severe and life-threatening.

Understanding the Causes: Portal Hypertension

The vast majority of esophageal varices, over 90%, are caused by a condition called portal hypertension. The portal vein is a major blood vessel that carries nutrient-rich blood from the digestive organs (stomach, intestines, spleen, pancreas) to the liver for processing. In portal hypertension, the pressure within this portal vein system becomes significantly elevated.

This increased pressure forces blood to seek alternative routes through smaller, less capable veins. These smaller veins, including those in the lining of the esophagus, become engorged and distended as they try to accommodate the excess blood flow. Over time, these engorged veins can develop into esophageal varices.

The Liver's Role: Cirrhosis as the Primary Culprit

The most common underlying cause of portal hypertension, and consequently esophageal varices, is liver cirrhosis. Cirrhosis is a late stage of scarring (fibrosis) of the liver caused by many forms of liver diseases and conditions, such as chronic alcoholism and chronic viral hepatitis (Hepatitis B and C).

When the liver is scarred and damaged by cirrhosis, its normal structure is disrupted. This disruption impedes the smooth flow of blood through the liver. The resistance to blood flow within the scarred liver causes pressure to build up in the portal vein, leading to portal hypertension. Chronic alcohol abuse is responsible for a significant percentage of cirrhosis cases worldwide, making it a leading indirect cause of esophageal varices.

Other Contributing Factors to Portal Hypertension

While liver cirrhosis is the most frequent cause, portal hypertension can arise from other conditions that obstruct blood flow to or within the liver:

Blood Clots: A blood clot in the portal vein (portal vein thrombosis) or hepatic veins (Budd-Chiari syndrome) can block blood flow and increase pressure.
Schistosomiasis: This parasitic infection, common in tropical and subtropical regions, can damage the liver and lead to portal hypertension.
Congenital Abnormalities: In rare cases, individuals may be born with abnormalities in the portal vein system that lead to increased pressure.
Gastrointestinal Conditions: Certain conditions affecting the spleen or pancreas can also contribute to increased pressure in the portal system.

When Varices Become Dangerous: Bleeding

Esophageal varices themselves often do not cause any noticeable symptoms. The danger arises when these swollen veins rupture and bleed. This bleeding can be sudden and profuse, leading to:

Vomiting blood (hematemesis), which may be bright red or look like coffee grounds.
Black, tarry stools (melena) due to digested blood.
Anemia and its symptoms (fatigue, weakness, shortness of breath).
In severe cases, hypovolemic shock (a life-threatening condition caused by significant blood loss), characterized by low blood pressure, rapid heart rate, dizziness, and confusion.

The risk of bleeding is directly related to the size of the varices and the severity of the underlying liver disease. Patients with larger varices or more advanced cirrhosis are at a higher risk of experiencing a variceal hemorrhage.

Diagnosis and Management

Diagnosis of esophageal varices is typically made through an upper endoscopy (esophagogastroduodenoscopy or EGD), a procedure where a flexible tube with a camera is inserted down the throat to visualize the esophagus, stomach, and duodenum. If varices are found, their size and the presence of red marks (which indicate a higher risk of bleeding) are assessed.

Management focuses on preventing bleeding and treating it if it occurs. This may involve medications to reduce portal pressure (like beta-blockers), endoscopic treatments to band or reduce the varices, or in severe cases, surgical procedures like a transjugular intrahepatic portosystemic shunt (TIPS) or liver transplantation.