Can cancer or chemotherapy patients get vaccinated?

Last reviewed: 2026-06-14

Quick answer

Yes — but the timing and choice of vaccine must be decided by your treating doctor or oncologist. During cytotoxic chemotherapy the body's immune response is suppressed, so vaccination is generally not recommended — the main exception is the inactivated influenza vaccine. Live (attenuated) vaccines are contraindicated when the immune system is suppressed. How long to wait after treatment before vaccinating depends on the type of therapy and the type of vaccine (for example, after anti-B-cell antibody therapy it may be six months or more before inactivated vaccines). Cancer patients face higher risk from infections, so vaccinating at the right time matters all the more — work out a personalised plan with your oncologist.

For a cancer patient, whether to vaccinate isn't a simple yes or no — it's "at the right time, with the right vaccine, as decided by your doctor."

During chemotherapy: a suppressed response

Cytotoxic chemotherapy suppresses the immune system, so the body responds less well to vaccines. Vaccination during chemotherapy is therefore generally not recommended — the main exception is the inactivated influenza vaccine, because flu poses a serious threat to cancer patients and this vaccine contains no live virus, making it relatively safe.

Live vaccines: contraindicated

Live attenuated vaccines (for example, the nasal live attenuated flu vaccine) are contraindicated while the immune system is suppressed and should not be given. Inactivated and recombinant vaccines contain no live pathogen and are relatively safe, though the protection they generate during treatment may be weaker.

How long to wait after treatment?

There's no single answer — it depends on the therapy and the vaccine. For instance, after anti-B-cell antibody therapy (a treatment that affects antibody production), it may be six months or more before inactivated vaccines, to allow an adequate response. The exact wait must be judged by your treating doctor.

Why it still matters

If a cancer patient catches flu, pneumococcal disease and the like, the risk of complications is far higher than for the general population. So the real question isn't "should I vaccinate?" but "when, and with which vaccine, is safest and most effective?" Ideally, discuss a vaccination plan with your oncologist before treatment begins; if you're already in treatment, raise it so your doctor can arrange it for you.

This article is general information and is not a substitute for professional medical advice. Discuss any vaccination plan with your oncologist or treating doctor.

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