Estramustine (Estracyt)

Estramustine is made from two types of drugs combined

• A hormone called oestrogen
• A chemotherapy drug called nitrogen mustard

Estramustine has been used for some years to treat advanced prostate cancer. Your doctor may suggest it if your prostate cancer is no longer responding to hormone treatment.

We don't know exactly how this drug works. We think it may stop cancer cells from separating into 2 new cells, so it stops tumours from growing. It may also block hormones in the body from encouraging the cancer cells to grow.

Estramustine comes as 140mg capsules. You should take these 1 hour before meals or 2 hours after, with plenty of water. Do not take estramustine with milk, anti acid medicines, or foods high in calcium.  All these can interfere with absorbing the drug into your body. Some heart medicines called ACE inhibitors can interact with estramustine. Tell your doctor if you are taking heart medicines. 

It is very important that you take tablets according to the instructions your doctor or pharmacist gives you. You should take the right dose, not more or less. And never stop taking a cancer drug without talking to your specialist first.

It is also important to store your tablets in a safe place away from children. Take unused tablets back to the pharmacy.

You usually have chemotherapy as a course of several cycles of treatment. You take the estramustine capsules in 3 or 4 doses daily. A typical plan is to take the capsules daily for 6 weeks, followed by a 2 week break. To find out more about the way chemotherapy treatment is planned, click on planning chemotherapy.

The side effects associated with estramustine are listed below. You can use the links (underlined) to find out more about each side effect. Where there is no link, please see our cancer drugs side effect section or click on search at the top of the page.

More than 10 in every 100 people have one or more of these.

• Feeling or being sick can happen within 2 hours of taking the drug – it is usually mild and easily controlled with anti sickness injections and tablets. Some people can have severe vomiting for 6 to 8 weeks after starting this drug. This can be difficult to control. Let your doctor or nurse know if it happens. If you are sick within 2 hours of taking estramustine, don't take another dose but tell your doctor when you next see them
• Breast tenderness or enlargement (gynaecomastia) happens in roughly half the people treated – men may have 1 or 2 radiotherapy treatments to the breast area to help prevent this
• Diarrhoea happens in about 2 out of 10 (20%) people – drink plenty of fluids and if it becomes severe or lasts more than a day or two, tell your doctor or nurse

Between 1 and 10 in every 100 people have one or more of these.

• Lowered interest in having sex (libido) and difficulty in getting an erection (impotence)
• Loss of fertility – you may not be able to father a child after treatment with this drug. It is important to talk to your doctor about your fertility before starting treatment
• Estramustine may have a harmful effect on a developing baby – it is not advisable to become pregnant or father a child if you are having this drug, so talk about contraception with your doctor or nurse before having the treatment
• Dry, itching skin or a rash
• Fluid retention leading to swollen hands or feet

Fewer than 1 in 100 people have these.

A temporary drop in the number of blood cells made by the bone marrow, causing

• Increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery
• Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
• Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia)

Some of these side effects can be life threatening, particularly infections. You should contact your treatment centre if you have any of these side effects. Your doctor will check your blood counts regularly to see how well your bone marrow is working.

Other rare side effects include

• Heart problems
• Difficulty sleeping (insomnia)
• Increased risk of blood clots (thrombosis)
• Other medical conditions such as diabetes and kidney problems can be made worse by taking estramustine – tell your doctor if you have any other health problems

The side effects above may be mild or more severe. A side effect may get better or worse through your course of treatment, or more side effects may develop as the course goes on. This depends on

• How many times you've had the drug before
• Your general health
• The amount of the drug you have (the dose)
• Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them. Your chemotherapy nurse, clinic or ward nurse will give you a contact number. You can ring if you have any questions or problems. They can give you advice or reassure you. If in doubt, call them.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and over the counter remedies – some drugs can react together.

You should not have immunisations with live vaccines while you are having this treatment or for at least 6 months afterwards. In the UK, live vaccines include rubella, mumps, measles (usually given together as MMR), BCG and yellow fever. You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered.

It is safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with oral vaccines, but not many people in the UK have oral vaccines now. So there is usually no problem in being with any baby or child who has recently had any vaccination in the UK. You might need to make sure that you aren't in contact with anyone who has had oral polio, cholera or typhoid vaccination recently, particularly if you live abroad.