Conditions and symptoms
What Is Chronic Hepatitis B? Liver Infection Explained
Chronic hepatitis B · say it: KRON-ik hep-uh-TY-tis BEEAlso written: CHB, chronic HBV, chronic hepatitis B virus infection, HBV
Short answer
Chronic hepatitis B is a long-lasting liver infection with the hepatitis B virus, defined as infection lasting more than six months.
What it means
Hepatitis B is a virus that infects the liver. It spreads through blood and other body fluids, including from parent to baby at birth, through sex and through shared needles. When the infection lasts longer than six months, it is called chronic hepatitis B. Many people with chronic infection feel well for years, but over time it can lead to liver scarring (cirrhosis) and liver cancer, which is why regular monitoring matters. It can be prevented with a vaccine.
Chronic hepatitis B appears on labels in several ways. Antiviral medicines list it as their use and carry a boxed warning that stopping them can cause a severe flare of hepatitis, so they should not be stopped without a doctor's plan. Labels for chemotherapy, some antirheumatic and biologic medicines, and some other treatments warn about hepatitis B reactivation, where a quiet infection becomes active again, and advise testing before treatment.
Chronic hepatitis B is different from acute hepatitis B, the first months of infection, which some adults clear on their own. It is also different from hepatitis A and C, which are other viruses.
Where you may see it
- Boxed warnings on hepatitis B antiviral labels
- Hepatitis B reactivation warnings on chemotherapy and biologic labels
- Blood test reports (HBsAg, HBV DNA, liver enzymes)
📄 How it looks on a report
Severe acute exacerbations of hepatitis B have been reported in patients who have discontinued anti-hepatitis B therapy.
🙅 What it does not mean
- Feeling well does not mean chronic hepatitis B is inactive; regular tests are still needed.
- It is not spread by casual contact such as hugging or sharing food.
- The reactivation warning on other medicines does not mean you cannot have them; it means testing and monitoring first.
🗒️ Questions to ask your doctor
💊 Medicines whose labels mention “Chronic hepatitis B”
Plain-English explanations of each medicine, from its official FDA label.
- Lamivudine
An antiviral medicine of the nucleoside analogue reverse transcriptase inhibitor type, used here for hepatitis B
- Tenofovir Disoproxil Fumarate
A nucleotide analog medicine. The label calls it an HIV-1 reverse transcriptase inhibitor and an HBV reverse transcriptase inhibitor. The FDA class is not listed.
🔗 Read more from trusted sources
- “Chronic hepatitis B” on MedlinePlus ↗
US National Library of Medicine
Seeing this word on your own report? Get every line of it explained, free.
Explain my report🧩 Related words
🔎 Look up another word
More words: conditions and symptoms
General information about a medical word, not advice about your own results. Ask the clinician who ordered the test what it means for you.