Rituximab and hepatitis B: what to know

Rituximab changes B cells, part of the immune system. If hepatitis B virus is present now or has been encountered in the past, reduced immune surveillance can permit the virus to become active again. Reactivation may occur during treatment or after it, and liver inflammation can be serious even when a person felt well beforehand. [Hepatitis B](/conditions/hepatitis-b/) screening usually involves blood tests that look for current infection and evidence of past exposure. A positive result does not automatically mean rituximab cannot be used; it means the plan needs specialist input.

Tell the treating team about any past hepatitis B diagnosis, vaccination, liver illness or previous antiviral treatment. Ask what screening is needed before the first infusion. Depending on the results, a clinician may recommend antiviral medicine, regular liver blood tests and monitoring during treatment and for a period afterwards. Do not stop prescribed antiviral medicine or miss planned tests. A [Liver Function Test](/treatments/diagnostics-and-screening/liver-function-test/) can help detect liver inflammation, but it does not replace hepatitis B-specific testing. [Hepatitis B Vaccination](/treatments/preventive-care-and-vaccination/hepatitis-b-vaccination/) may be discussed when appropriate.

Contact the treatment team urgently if you develop yellowing of the skin or eyes, new [Dark Urine](/symptoms/dark-urine/), severe nausea, vomiting, abdominal swelling, unusual bleeding or marked [Fatigue](/symptoms/fatigue/). Seek emergency help for confusion, collapse or severe illness. Do not wait for the next infusion appointment if these symptoms appear.

Have I been tested for current or past hepatitis B? Do I need antiviral protection? How often will my liver and virus markers be checked? How long should monitoring continue after rituximab?