Diethylstilbestrol

Diethylstilbestrol is a hormonal therapy drug. It is used to treat advanced prostate cancer when other treatments are not suitable or no longer working.

It is best to read this information with our general information about hormonal therapy and  the type of cancer you have.

Your cancer team will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

This information is correct at time of publishing. But sometimes the types of cancer this treatment is used for, or treatment side effects, may change between revision dates.

You can talk to your cancer team if you want more detailed information about this treatment. Or visit the electronic Medicines Compendium (eMC) website, which has patient information leaflets (PIL) for individual drugs.

You have diethylstilbestrol as tablets you can take at home.

During your treatment, you will meet someone from your cancer team, such as a:

• cancer doctor
• specialist nurse
• specialist pharmacist.

This is who we mean when we mention doctor, nurse or pharmacist in this information.

Your cancer team will discuss your treatment plan with you.

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

• swallow the tablets whole with a glass of water
• do not chew, break or crush them
• take them at the same time every day.

If you forget to take the tablets, take the missed dose as soon as possible within the same day. If a full day has passed, do not take a double dose.

Other things to remember about your tablets:

• Keep them in the original package and at room temperature, away from moisture, heat and direct sunlight.
• Keep them safe, where children cannot see or reach them.
• If you are sick (vomit) just after taking them, do not take an extra dose. Take your next dose at the usual time.
• Make sure anybody who is pregnant does not handle diethylstilbestrol tablets, unless they wear gloves.
• Get a new prescription before you run out, and make sure you have plenty for holidays.
• Do not throw away unused tablets. Return them to a pharmacy.

Your cancer team may also give you other medicines to take home. Take all your medicines exactly as they tell you to. Do not stop taking any of your medicines unless your doctor tells you to.

This treatment may contain lactose. If you have a lactose allergy or intolerance, ask your doctor, nurse or pharmacist for more information.

Sometimes fluid can build up in your legs and ankles. This can cause swelling and is called oedema. If you have any swelling, tell your doctor, nurse or pharmacist. If your ankles and legs swell, it can help to put your legs up on a foot stool or cushion.

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. It may cause a rash, which may be itchy. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using soap-free cleansers and unperfumed moisturising cream every day.

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. Changes to your skin usually improve when treatment ends.

You may gain weight when you are having this treatment. Eating healthily and being active can help you keep to a healthy weight. 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.

This treatment may affect how your liver works. This is usually mild. You will have blood tests to check how well your liver is working.

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.

Cancer and some cancer treatments, such as diethylstilbestrol, can increase the risk of a blood clot. You may be given low-dose aspirin tablets to help prevent blood clots.

Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

• throbbing pain or swelling in a leg or arm
• reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
• suddenly feeling breathless or coughing.

Always call 999 if you have:

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

This treatment might cause an allergic reaction. But this is not common. Signs of a reaction can include:

• a skin rash or itching
• feeling breathless or wheezy
• swelling of your face, mouth or throat.

If you feel unwell or have any of these signs, contact the hospital straight away on the 24-hour number. Do not take any more of this treatment until you have checked with them.

Always call 999 if swelling happens suddenly or you are struggling to breathe.