Diethylstilbestrol

Hormones are chemicals that our bodies make. Hormones act as messengers and help control how cells and organs work. Hormonal therapies are drugs that change the way hormones are made or how they work in the body.

Most prostate cancers need the hormone testosterone to grow. Almost all testosterone is made by the testicles. Diethylstilbestrol reduces the amount of testosterone made by your body. This reduces testosterone levels and may help to control the cancer.

Diethylstilbestrol comes as tablets you can take at home. Your nurse or doctor will talk to you about your treatment plan. 

Always take the tablets exactly as explained. This is important to make sure they work as well as possible for you. Make sure you:

• swallow them whole, with a glass of water.
• take them at the same time every day.

If you forget to take the tablets, you should take the missed dose as soon as possible within the same day. 

Other things to remember about your tablets:

• Keep them in the original package and at room temperature, away from heat and direct sunlight
• Keep them safe and out of sight and reach of children.
• If you are sick just after taking the tablets, contact your healthcare team. Do not take another dose.
• Diethylstilbestrol tablets should not be handled without protection by anyone who is pregnant. 
• Get a new prescription before you run out of tablets, and make sure you have plenty for holidays.
• If your treatment is stopped, return any unused tablets to the pharmacist. 

Your nurse or pharmacist may also give you other medicines to take home. Take all your medicines exactly as they have been explained to you. Do not stop taking any of your medicines unless your doctor tells you to.

Fluid can sometimes build up in your legs and ankles. This can cause swelling. This is known as oedema. Tell your doctor or nurse if you have any swelling. If your ankles and legs swell, it can help to rest your legs on a foot stool or cushion. The swelling usually gets better after your treatment ends.

This is usually mild. If you need anti-sickness drugs, your doctor can prescribe them.

Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest between activities.

Being physically active can help to manage tiredness and give you more energy. It also:

• helps you sleep better
• reduces stress
• improves your bone health.

If you feel sleepy, do not drive or operate machinery.

This treatment may cause swelling and tenderness of your breast tissue. This is called gynaecomastia. To prevent this, some people have 1 or more low-dose radiotherapy treatments to the chest before treatment starts. Another type of hormonal drug might be used to treat the breast swelling. Your doctor can give you more advice.

It is common to lose your sex drive and have erection difficulties with hormonal therapy. Hormonal therapy may also make your penis shorter and your testicles smaller. 

Your doctor can prescribe drugs and treatments to help with erection difficulties. These will not increase your sex drive. But they might work, even with a low sex drive. 

Things can improve a few months after you stop taking the drug. But it depends on how long you take hormonal therapy, and what other treatments you have had. Some people continue to have problems after treatment ends.

This treatment may cause headaches. If this happens, tell your doctor or nurse. They can give you painkillers.

If you had migraines (a severe type of headache) before starting diethylstilbestrol, these may get worse. If you have more headaches than usual, let your doctor know.

This treatment may affect your skin. If your skin feels dry, try using an unperfumed moisturising cream every day. The treatment may cause a rash, which may be itchy.  Some people may get red bumps (nodules) on their skin.

Areas of your skin might become darker. Protecting your skin from the sun may help reduce this. Use a high factor sun cream (SPF 30 or above) before going out in the sun.

Always tell your doctor or nurse about any skin changes. They can give you advice and may prescribe creams or medicines to help.

This treatment may make you put on weight. You may also lose some muscle strength. Eating healthily and being active can help. Your doctor, nurse or dietitian can give you more advice.

You may feel low or depressed, or have mood swings, during this treatment. Talking to family and friends about how you feel might help. If mood changes last for more than a few weeks, tell your doctor, nurse or pharmacist. They can talk to you about different ways to manage low mood or depression.

Your blood pressure should be checked regularly while you are taking this drug. If you develop high blood pressure, your doctor will stop this treatment.

This treatment can raise your blood sugar levels and increase the risk of diabetes. 

Signs of raised blood sugar include:

• feeling thirsty
• needing to pass urine (pee) more often than usual
• feeling more tired than usual. 

Tell your doctor or nurse if you have these symptoms. They can do tests to check your blood sugar level and give you advice.

If you already have diabetes, your blood sugars may be higher than usual. You may need to check them more often, or make changes to your diabetic treatment. Your diabetic doctor or nurse will talk to you about how to manage this.

Rarely, this drug can cause gallstones and jaundice. Tell your doctor straight away if you notice your skin or the whites of your eyes becoming yellow

If you wear contact lenses, diethylstilbestrol might make your eyes uncomfortable. Tell your doctor if you experience this. They may prescribe eye drops to help. Tell your doctor if this problem does not get better.

You may get pain in your muscles or joints. If this happens, tell your doctor or nurse. They can give you advice and painkillers or other drugs to help. Being physically active and keeping to a healthy weight may help with the pain. It can keep your joints flexible and reduce stress on them. If the pain does not get better, tell your doctor or nurse. They may talk to you about changing to a different hormonal drug.

Cancer and some treatments, such as diethylstilbestrol, can increase the risk of a blood clot. To help prevent blood clots, your doctor may prescribe a low dose of aspirin during this treatment. 

Symptoms of a blood clot include:

• throbbing pain, redness or swelling in a leg or arm
• suddenly feeling breathless or coughing
• sharp chest pain, which may be worse when you cough or take a deep breath. 

If you have any of these symptoms, contact the hospital straight away on the 24-hour contact number you have been given. If you cannot get through to your doctor, call the NHS urgent advice number on 111.

A blood clot is serious, but it can be treated with drugs that thin the blood (anticoagulants). Your doctor or nurse can give you more information. 

You can help reduce the risk of developing a blood clot by:

• staying active during treatment 
• drinking plenty of fluids, especially water.

This drug contains a colouring agent called sunset yellow that might cause an allergic reaction. If you have ever had an allergic reaction before, tell your doctor. Signs of a reaction can include:

• feeling hot or flushed 
• a skin rash
• itching
• shivering
• feeling dizzy
• a headache
• feeling breathless.

If you feel unwell or have any of these signs, tell a doctor or nurse straight away. Do not take any more of this treatment until you have spoken to them.

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