Gastrointestinal Symptoms of COVID-19

Dr. Panwad Munchit
Gastroenterologist and Hepatologist

     While COVID-19 is primarily known for its impact on the respiratory system, I would like to highlight that recent studies indicate the virus can also affect the gastrointestinal system and liver.

Entry of COVID-19 into the Digestive System and Liver

     The entry point for the COVID-19 virus into human cells is through a receptor called ACE2 (Angiotensin-Converting Enzyme 2). This receptor is predominantly found in the lungs and respiratory epithelium, which led to the early assumption that the virus primarily enters the body through the respiratory system. However, advancements in medical research have revealed that ACE2 receptors are also abundant in gastrointestinal epithelial cells and bile duct lining cells.

     This discovery has led to the current understanding that if the virus invades gastrointestinal epithelial cells, it can disrupt normal cell functions such as absorption and increase the permeability of these cells, allowing foreign substances to enter more easily.

Gastrointestinal Symptoms of COVID-19

The most common gastrointestinal symptoms associated with COVID-19 include:

• Diarrhea, which is the most frequently reported symptom
• Nausea and vomiting, which are moderately common
• Abdominal pain, which is less commonly observed

Symptom Progression

     These gastrointestinal symptoms typically appear within the first 1–2 days, often preceding respiratory symptoms such as fever, shortness of breath, and chest discomfort. In some cases, the gastrointestinal manifestations may be as severe as those seen in patients with critical respiratory involvement.

COVID-19 Infection in Patients with Pre-existing Liver Disease

     Statistics show that 14–57% of patients infected with COVID-19 exhibit elevated liver enzymes (AST, ALT), typically ranging from 1 to 3 times the normal values. However, these changes are often asymptomatic and tend to resolve without specific treatment. In patients with pre-existing chronic liver conditions, particularly chronic viral hepatitis, the liver enzyme abnormalities may exceed this range and can result in worsened liver function post-infection.

At present, there have been no confirmed reports of liver failure-related death caused directly by COVID-19, so a definitive link cannot yet be established.

Preventive Measures for Chronic Liver Disease Patients

For patients receiving immunosuppressive therapy or those with chronic liver diseases during the COVID-19 pandemic, in addition to standard precautions like social distancing and frequent handwashing, the following recommendations are advised:

• Continue regular medications for existing health conditions.
• Use paracetamol (acetaminophen) for fever relief at a dose not exceeding 2 grams per day (up to 4 tablets/day).
• Avoid NSAIDs, especially ibuprofen, which may affect liver function.
• Consume freshly cooked, hygienic food and always wash hands thoroughly before eating to minimize viral contamination.
• Attend scheduled medical appointments as necessary—most physicians will only arrange follow-ups when essential.

Commitment to Safety, Ramkhamhaeng Hospital

     Ramkhamhaeng Hospital has implemented stringent infection control protocols to ensure the safety of all patients and staff, fostering a secure and reassuring environment for those seeking medical care.