Capecitabine

Capecitabine is a prescription medication used to treat breast cancer and cancer of the colon or rectum. Capecitabine belongs to a group of drugs called antimetabolites which work by interfering with DNA production, stopping cells from multiplying.

This medication comes in tablet form and is usually taken twice daily, within 30 minutes after the end of a meal.

Swallow tablets whole. Do not cut or crush tablets.

Common side effects include diarrhea, nausea, vomiting, and mouth sores.

DPD is the enzyme responsible for breaking down capecitabine in the body. Some patients lack the DPD enzyme. If you lack or have less of the DPD enzyme, you may be more likely to experience side effects more quickly or severely once you begin treatment with capecitabine. Tell your doctor if you have ever been told you lack the DPD enzyme.

Your doctor may decide to temporarily or permanently stop treatment with capecitabine depending on the severity of side effects. There are no exact dosing guidelines based on the results of any particular DPD test.

Capecitabine is a prescription medication used to treat:

• cancer of the colon after surgery
• cancer of the colon or rectum (colorectal cancer) that has spread to other parts of the body (metastatic colorectal cancer). 
• breast cancer that has spread to other parts of the body (metastatic breast cancer) together with another medicine called docetaxel (Taxotere)
• breast cancer that has spread to other parts of the body and has not improved after treatment with other medicines such as paclitaxel (Taxol) and anthracycline-containing medicine such as Adriamycin and doxorubicin.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Capecitabine may be found in some form under the following brand names:

• Xeloda

The most common side effects of capecitabine are:

• diarrhea, nausea, vomiting, sores in the mouth and throat (stomatitis), stomach area pain (abdominal pain), upset stomach, constipation, loss of appetite, and too much water loss from the body (dehydration). These side effects are more common in patients age 80 and older.
• hand-and-foot syndrome (palms of the hands or soles of the feet tingle, become numb, painful, swollen or red), rash, dry, itchy or discolored skin, nail problems, and hair loss
• tiredness, weakness, dizziness, headache, fever, pain (including chest, back, joint, and muscle pain), trouble sleeping, and taste problems These side effects may differ when taking capecitabine with docetaxel (Taxotere). Please consult your doctor for possible side effects that may be caused by taking capecitabine with docetaxel (Taxotere).

Stop taking capecitabine immediately and contact your doctor right away if you have the side effects listed below, or other side effects that concern you.

• Diarrhea - Tell your doctor if you have an additional 4 bowel movements each day beyond what is normal or any diarrhea at night
• Vomiting - Tell your doctor if you vomit more than once in a 24-hour time period
• Nausea - Tell your doctor if you lose your appetite, and the amount of food you eat each day is much less than usual
• Stomatitis: Tell your doctor if you have pain, redness, swelling or sores in your mouth
• Hand-and-Foot Syndrome - Tell your doctor if you have pain, swelling or redness of your hands or feet that prevents normal activity
• Fever or Infection - Tell your doctor if you have a temperature of 100.5°F or greater, or other signs of infection Your doctor may tell you to lower the dose or to stop capecitabine treatment for a while. If caught early, most of these side effects usually improve after you stop taking capecitabine. If they do not improve within 2 to 3 days, call your doctor again. After your side effects have improved, your doctor will tell you whether to start taking capecitabine again and what dose to take. Adjusting the dose of capecitabine to be right for each patient is an important part of treatment.

Capecitabine may increase the effect of other medicines used to thin your blood such as warfarin (Coumadin). It is very important that your doctor knows if you are taking a blood thinner such as warfarin because capecitabine may increase the effect of this medicine and could lead to serious side effects. If you are taking blood thinners and capecitabine, your doctor needs to check more often how fast your blood clots and change the dose of the blood thinner, if needed.

If you take phenytoin (Dilantin), your doctor may need to test the levels of phenytoin in your blood more often or change your dose of phenytoin.

Do not take this medication if you:

• are nursing a baby. Tell your doctor if you are nursing. Capecitabine may pass to the baby in your milk and harm the baby.
• are allergic to 5-fluorouracil
• are allergic to capecitabine or to any of the ingredients in capecitabine
• have been told that you lack the enzyme DPD (dihydropyrimidine dehydrogenase)

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of capecitabine, there are no specific foods that you must exclude from your diet when receiving capecitabine.

Tell your doctor if you:

• take a blood thinner such as warfarin (Coumadin). This is very important because capecitabine may increase the effect of the blood thinner. If you are taking blood thinners and capecitabine, your doctor needs to check more often how fast your blood clots and change the dose of the blood thinner, if needed.
• take phenytoin (Dilantin). Your doctor needs to test the levels of phenytoin in your blood more often or change your dose of phenytoin.
• are pregnant or think you may be pregnant. capecitabine may harm your unborn child.
• have kidney problems. Your doctor may prescribe a different medicine or lower the capecitabine dose.
• have liver problems. You may need to be checked for liver problems while you take capecitabine.
• have heart problems because you could have more side effects related to your heart.
• take the vitamin folic acid. It may affect how capecitabine works.

Tell your doctor if you are pregnant or think you may be pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

This medication falls into category D. Capecitabine may harm your unborn child. Use effective birth control while taking capecitabine.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if capecitabine is excreted in human breast milk or if it will harm your nursing baby.

• Take capecitabine exactly as your doctor tells you to. Your doctor will prescribe a dose and treatment plan that is right for you.
• Your doctor may want you to take both 150 mg and 500 mg tablets together for each dose. If so, you must be able to identify the tablets.
• Taking the wrong tablets could cause an overdose (too much medicine) or underdose (too little medicine). The 150 mg tablets are light peach in color with 150 on one side. The 500 mg tablets are peach in color with 500 on one side.
• Your doctor may change the amount of medicine you take during your treatment.
• Your doctor may prescribe capecitabine tablets with docetaxel (Taxotere) injection.
• Capecitabine is taken in 2 daily doses, a morning dose and an evening dose
• Take capecitabine tablets within 30 minutes after the end of a meal (breakfast and dinner)
• Swallow capecitabine tablets whole with water
• If you miss a dose of capecitabine, do not take the missed dose at all and do not double the next dose. Instead, continue your regular dosing schedule and check with your doctor.
• Capecitabine is usually taken for 14 days followed by a 7-day rest period (no drug), for a 21-day cycle. Your doctor will tell you how many cycles of treatment you will need.
• If you take too much capecitabine, contact your doctor or local poison control center or emergency room right away.

What should I avoid while taking capecitabine?

• Women should not become pregnant while taking capecitabine. Capecitabine may harm your unborn child. Use effective birth control while taking capecitabine. Tell your doctor if you become pregnant.
• Do not breastfeed. Capecitabine may pass through your milk and harm your baby.
• Men should use birth control while taking capecitabine.

Take capecitabine exactly as prescribed by your doctor. Follow the directions on your prescription label carefully. Your doctor will determine the best dose for you.

Standard Starting Dose

In Combination With Docetaxel (Metastatic Breast Cancer)

• The recommended dose of capecitabine is 1250 mg/m² twice daily for 2 weeks. This is followed by a 1-week rest period.
• You will be carefully monitored for toxicity.
• Doses of capecitabine should be adjusted as necessary to accommodate tolerance to treatment.

If you take too much capecitabine call your healthcare provider or local Poison Control Center or seek emergency medical attention right away.

If capecitabine is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if an overdose is suspected, seek emergency medical attention.

WARNING: CAPECITABINE-WARFARIN INTERACTION

Capecitabine Warfarin Interaction: Patients receiving concomitant capecitabine and oral coumarin-derivative anticoagulant therapy should have their anticoagulant response (INR or prothrombin time) monitored frequently in order to adjust the anticoagulant dose accordingly. A clinically important Capecitabine-Warfarin drug interaction was demonstrated in a clinical pharmacology trial. Altered coagulation parameters and/or bleeding, including death, have been reported in patients taking Capecitabine concomitantly with coumarin-derivative anticoagulants such as warfarin and phenprocoumon. Postmarketing reports have shown clinically significant increases in prothrombin time (PT) and INR in patients who were stabilized on anticoagulants at the time capecitabine was introduced. These events occurred within several days and up to several months after initiating capecitabine therapy and, in a few cases, within 1 month after stopping capecitabine. These events occurred in patients with and without liver metastases. Age greater than 60 and a diagnosis of cancer independently predispose patients to an increased risk of coagulopathy.