Chemotherapy when you have high blood pressure

Yes. High blood pressure is one of the most common long-term conditions among people starting cancer treatment, and on its own it very rarely stops chemotherapy. Most people carry on with their usual blood pressure care, with any changes decided by their doctors. What matters is knowing that treatment can push blood pressure in both directions. Some cancer medicines raise it. Targeted medicines that block blood vessel growth, such as bevacizumab, sunitinib, pazopanib and lenvatinib, commonly raise blood pressure, sometimes sharply. Steroid medicines given with chemotherapy, some anti-inflammatory painkillers and medicines used to boost red blood cells can also raise it. Pain, anxiety and poor sleep add to this.

At the same time, chemotherapy can lower blood pressure. Sickness, vomiting, diarrhoea and poor drinking cause dehydration, and blood pressure tablets that were suitable before may then make you dizzy or faint, particularly when standing up. Water tablets can worsen dehydration. Kidney changes during treatment can affect how blood pressure medicines work. This is why your doctors may temporarily adjust your tablets during treatment weeks, and why you should report dizziness as well as headaches.

Home blood pressure monitoring is very helpful. A validated automatic arm monitor, used sitting quietly after a few minutes of rest, gives useful readings. Your team will tell you how often to check and which readings to report, especially if you are on a medicine known to raise blood pressure. Well-controlled blood pressure protects your heart, kidneys and brain during treatment and helps avoid delays to cancer treatment. Never start, stop or change a blood pressure medicine on your own.

Tell your team about all your tablets

Bring a list of every blood pressure and heart medicine you take.

Check at home if advised

A simple arm monitor and a written record help your team make safe decisions.

Report dizziness too

Low blood pressure from dehydration is common during treatment and needs attention.

It cannot tell you what your blood pressure target is, or how to change your tablets. These depend on your health, other conditions and cancer treatment, and must be decided by your doctors.

It also cannot tell you whether a specific cancer medicine is safe with your blood pressure. Your oncologist will consider this when planning treatment.

Targeted medicines need extra attention

If you are prescribed a medicine that blocks blood vessel growth, your team will usually want blood pressure well controlled before starting and checked regularly afterwards. Rises are common and usually manageable with blood pressure medicines chosen by your doctors. Occasionally, the cancer medicine is paused or reduced until blood pressure is controlled.

Blood pressure and the kidneys

High blood pressure can damage kidneys, and kidney problems can raise blood pressure. Some cancer medicines also cause protein to leak into urine. Urine and blood tests may be checked alongside blood pressure.

Salt, food and lifestyle

Limiting salty foods such as pickles, papad and packaged snacks, staying gently active as advised, sleeping well and avoiding tobacco all help blood pressure. During chemotherapy, eating enough matters, so ask a dietitian to balance salt advice with nutrition.

Herbal remedies and supplements

Some remedies, such as liquorice, can raise blood pressure or interact with medicines. Tell your team about everything you take.

After treatment

Blood pressure may settle once steroids or targeted medicines stop, and your doctor may review your tablets again.

Measuring at home correctly

Readings can be misleading if taken just after walking, eating, drinking tea or coffee, smoking, or while talking. Use the same arm each time, with the cuff on bare skin and the arm supported at heart level. Avoid checking during pain or distress unless your team asks you to. If a reading is unexpectedly high, rest for a few minutes and repeat before worrying. Bring your monitor to the clinic once so staff can check it against theirs.

Blood pressure tablets on sick days

When vomiting, diarrhoea or poor drinking cause dehydration, some blood pressure tablets can make dizziness and kidney strain worse. Many hospitals give patients a sick-day plan explaining which medicines to discuss with a doctor during such illness. Ask your team whether this applies to your tablets, but do not stop any medicine without advice.

Steroids and blood pressure

Steroid medicines given with chemotherapy can raise blood pressure and cause fluid retention. Effects usually settle after the steroids finish. If readings stay high, your doctor may review your tablets.

Protein in urine

Some targeted medicines that raise blood pressure can also cause protein to leak into urine, which may make urine frothy. Your team may test urine regularly and adjust treatment if needed.

Stress, sleep and blood pressure

Anxiety, poor sleep and pain all raise blood pressure temporarily. Relaxation techniques, gentle walks, regular sleep routines and good pain control can help. Talk to your team if worry or sleeplessness is affecting you.

Older people and falls

Older people are more prone to dizziness and falls when blood pressure drops on standing. Stand up slowly, sit on the bed edge for a moment first, and use support if needed.

Keeping your physician informed

Keep your regular physician informed about cancer treatment, as they know your blood pressure history and can help adjust tablets alongside the oncology team.

What to do next

Tell your oncologist about your blood pressure and medicines, ask whether any cancer medicine affects it, check at home as advised, keep a record, report dizziness and headaches, never change tablets on your own, and seek emergency help for warning signs.