Hormonal therapies

Some hormonal therapies increase the risk of heart problems.

In women, hormonal therapies used to treat breast cancer may increase the amount of cholesterol in the blood. Rarely, this may increase the risk of heart problems and blood clots, such as a deep vein thrombosis (DVT). They include tamoxifen, anastrazole (Arimidex®), exemestane (Aromasin®) and letrozole (Femara®).

In men, hormonal therapies to treat prostate cancer work by lowering testosterone levels. Low testosterone levels can cause a man to gain weight and increase the amount of cholesterol in their blood. This may also increase their risk of diabetes. All of these factors increase the risk of heart problems.

Working together to create information for you

We worked with British Heart Foundation to write our content on heart health.

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Back to Cancer treatment and your heart


A few chemotherapy drugs affect the heart. Your hospital team will talk to you about any risks of the drugs you’re having.


Radiotherapy only affects the heart if it’s in the area treated. Improvements in radiotherapy treatment have reduced the risk of problems.

Surgery for cancer

You’ll usually have tests to check your heart before you have an operation to treat a cancer.

Cancer research trials

If you take part in a clinical trial, you will have regular checks for any side effects.

Managing heart problems

If you have heart problems during cancer treatment, your doctors will help you decide on the best way to manage them.