Chemotherapy when you have hepatitis B or C

Usually, yes, but hepatitis B needs to be found and managed before treatment starts. Many people carry hepatitis B without knowing it, because the virus can stay quiet in the liver for years. Chemotherapy, steroid medicines and some targeted treatments, particularly rituximab used for lymphoma, weaken the immune system's control over the virus. The virus can then multiply rapidly, a flare-up known as reactivation, which can cause severe liver inflammation and, in some people, liver failure. Reactivation can happen even in people who cleared hepatitis B in the past and have no active infection. It can also delay or interrupt cancer treatment. The good news is that it is largely preventable.

Prevention starts with a blood test. International cancer and liver guidelines recommend that people starting chemotherapy, especially treatments known to carry higher risk, are tested for hepatitis B, and often for hepatitis C and HIV too. If the test shows current or past hepatitis B, your doctor may prescribe an antiviral medicine, such as tenofovir or entecavir, to be taken throughout chemotherapy and for a period afterwards. Your liver tests, and sometimes the amount of virus in the blood, are checked regularly. Taking the antiviral every day as prescribed, and not stopping it without advice, is essential, because stopping too early can itself trigger a flare.

Hepatitis C behaves differently. Flare-ups during chemotherapy are less common and usually less severe than with hepatitis B, but they can happen, and hepatitis C can affect the liver's ability to handle cancer medicines. Modern tablet treatments can clear hepatitis C in most people, and your doctors will decide whether to treat it before, during or after chemotherapy, taking possible interactions into account. A liver specialist often helps plan this.

Screening is quick and important

A simple blood test before the first cycle can prevent a serious and avoidable complication.

Past infection still matters

Even if you were told you recovered from hepatitis B, tell your oncologist.

Liver tests guide treatment

Liver blood tests are checked before each cycle and more often if you have hepatitis.

It cannot tell you whether you need antiviral medicine, which one, or for how long. That depends on your test results, liver health and the cancer treatment planned, and must be decided by your doctors.

It also cannot interpret your hepatitis test results. Hepatitis B tests have several parts, and their meaning depends on the combination. Ask your doctor to explain yours.

Why people do not know they have hepatitis B

Hepatitis B is common in India, and many people were infected at birth or in early childhood without any symptoms. Some were told years ago and forgot, or were never told. Others cleared the virus but still carry traces that can reactivate. This is why screening is recommended for everyone starting higher-risk treatment, rather than only for people who think they may be affected.

Family and household

Hepatitis B spreads through blood and body fluids, not through sharing food or hugging. Household members and sexual partners can be tested and vaccinated. Avoid sharing razors or toothbrushes, and cover cuts.

Cost and access to antivirals

Antiviral medicines for hepatitis B are widely available in India, often at modest cost, and some government programmes provide hepatitis treatment. Ask your team or social worker about access, and make sure you never run out during treatment.

If a flare-up happens

Chemotherapy may be paused while the liver recovers, and antiviral treatment started or adjusted. Most people can resume cancer treatment once liver tests improve, but early detection is key.

Stigma and privacy

Some people fear judgement about hepatitis. It is a common medical condition, and your results are confidential. Being open with your treating team protects your health.

Rituximab and hepatitis B

Rituximab and similar medicines, used for many lymphomas and some other conditions, carry one of the highest risks of hepatitis B flare-up, even in people who only have signs of past infection. For these treatments, most guidelines advise either preventive antiviral medicine or very close monitoring, decided by your doctors. Flare-ups can occur months after the last dose, which is why follow-up continues after treatment ends.

Hepatitis B vaccination

People who test negative for hepatitis B and have never been vaccinated may be offered vaccination, although the response can be weaker during chemotherapy. Family members who are not immune can be vaccinated too.

Working with a liver specialist

A gastroenterologist or liver specialist can assess liver scarring, explain virus tests, choose antiviral treatment and decide on follow-up. If you already see one, tell them about your cancer treatment plan and ask them to write to your oncologist. If you do not, ask your oncologist whether a referral would help.

Keeping a supply of medicine

Running out of antiviral tablets during travel or festivals is a common problem. Keep a spare supply and refill early.

What to do next

Ask whether you have been tested for hepatitis B and C, tell your team about any past infection, take any prescribed antiviral every day without stopping on your own, attend liver tests, and report yellow eyes, dark urine or tummy swelling straight away.