Before taking tamoxifen

Before taking tamoxifen make sure your doctor or pharmacist knows:

• If you are pregnant, trying for a baby or breast-feeding.
• If you suffer from porphyria (a blood disorder).
• If you have problems with blood clots.
• If you are taking an hormonal form of contraceptive or hormone replacement therapy.
• If you suffer from unusual or irregular menstrual periods.
• If you are being treated for infertility and either you have had, or a close relative has had, a stroke or a blood clot on the lung.
• If you are taking other medicines, including those available to buy without a prescription, herbal or complementary medicines.
• If you have ever had an allergic reaction to this or any other medicine.

How to take tamoxifen

• Before beginning treatment, read the manufacturer's printed information leaflet.
• Take tamoxifen exactly as directed by your doctor. The usual dose for breast cancer is 20 mg each day. For the treatment of infertility the dose is usually 20 mg daily on the second, third, fourth and fifth days of your monthly cycle where the first day of the cycle is your first day of bleeding.
• Take tamoxifen at the same time each day. If you forget a dose take it as soon as you remember but only during that same day. Do not take a double dose on the next day to make up for a missed dose.

Getting the most from your treatment

• Before having surgery or any kind of medical treatment, including dental or emergency treatment, tell the doctor, surgeon, dentist, or other medical professional, that you are taking tamoxifen.
• Keep your regular appointments with your doctor and appointments for blood tests so your progress can be monitored.
• You must not get pregnant whilst taking tamoxifen. If you need advice about suitable contraception, ask your doctor or pharmacist.

Can tamoxifen cause problems?

Along with their useful effects all medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

• If you experience irregular or unusual vaginal bleeding, unusual vaginal discharge, pelvic pain or pressure, make an appointment to see your doctor as soon as possible.
• Taking tamoxifen may increase your chances of developing a deep vein thrombosis (DVT). The risk is increased if you have recently had surgery or have had a period of immobility. If you experience pain or swelling in the calf of one leg or sudden breathlessness contact your doctor immediately.
• If you develop difficulty breathing, swelling of the face, lips, tongue or throat, an itchy skin rash or skin peeling, flu-like symptoms or yellowing of the skin and eyes, contact your doctor as soon as possible.

If you experience these or any other worrying symptoms, which you think may be due to this medicine, discuss them with your doctor or pharmacist.

How to store tamoxifen

• Keep all medicines out of the reach and sight of children
• Store in a cool, dry place, away from direct heat and light

Important information about all medicines

References

• Manufacturer's PIL, Tamoxifen 10 mg, 20 mg & 40 mg Film-Coated Tablets, Wockhardt UK Ltd, electronic Medicines Compendium. Dated March 2007, accessed February 2010.
• British National Formulary; 58th Edition (September 2009) British Medical Association and Royal Pharmaceutical Society of Great Britain, London.