Capecitabine chemotherapy is used to treat metastatic colon or rectal cancer. It also serves as the best treatment for metastatic breast cancer. Capecitabine is classified as an antimetabolite. The trade name for this drug is Xeloda. It comes in a pill form.

Administration of Capecitabine

This is taken in the pill form orally after meals within 30 minutes. There should be a gap of at least 12 hours between two doses of this drug. These tablets are in two dosages- 150 mg and 500 mg. normally most doctors prescribe both these compositions and adjust the dose properly. These tablets should be swallowed with a glass of water not be crushed or chewed. Drugs given in chemotherapy must be taken in proper doses. Chemotherapy doses  should be taken in the right way.

The right dosage of Capecitabine depends on the doctor. Normally factors like height, weight, general health, other health problems, the type, and stage of the cancer are considered while determining the dose and schedule. Stages of the chemotherapy  are decided based on stage of the cancer.

Working of Capecitabine

Capecitabine is categorized as a called antimetabolite. Antimetabolites resemble some to normal substances within the cell. Hence, when penetrate the cells, the cells mistake them for their own substances and try to divide. However, they are unable to divide and this results in cell death.

Antimetabolites are cell cycle specific.  They attack the cells at very specific phases in the cycle and interfere with specific substances in the cell. They are classified based on the substances they interfere with. Capecitabine is a pyrimidine antagonist. Some other drugs in this category are 5-Fluorouracil, Floxuridine, Cytarabine and Gemcitabine.

Side Effects of Capecitabine Chemotherapy

• Fatigue
• Diarrhea
• Hand-foot syndrome (Palmar-plantar syndrome) that causes skin rash, pain and peeling of the skin on the palms and soles, redness and swelling. This can be controlled with medication. This usually starts within 15 days after infusion.
• Low counts of red blood cells leading to anemia
• Nausea and vomiting
• Dermatitis
• Elevated liver enzymes that is temporary increase in bilirubin levels

Some relatively uncommon side effects of Capecitabine are-

• Poor appetite
• Abdominal pain
• Low white blood cell count that hampers immunity
• Low platelet count that causes bruising and bleeding
• Mouth sores
• Peripheral neuropathy
• Swelling of the feet and ankles
• Fever
• Constipation
• Eye irritation that cause watery eyes, inflammation of the eyelids and redness
• Shortness of breath
• Headache
• Chest, back, muscle, joint and bone pain
• Dizziness
• Insomnia
• Cough
• Blood clots due to deep vein thrombosis.
• Excessive sleepiness, confusion and rarely seizures
• Loss of balance
• Nail changes
• Taste changes

Precautions for Capecitabine Chemotherapy

• Inform your doctor about any other medications or therapies you are taking or have taken in the past. This includes prescription, OTC medications, supplements, herbal remedies, alternative therapies, etc.
• Avoid use of antacids within 2 hours of taking Capecitabine.
• Inform your doctor if you are taking blood thinners like warfarin as these drugs also cause blood thinning.
• Capecitabine should not be recommended if you had a hypersensitivity reaction to fluorouracil.
• Do not receive any vaccinations without your doctor’s approval.
• Do not take aspirin without your doctor’s approval.
• Even males should practice safe sex by using barrier methods as this drug damages the sperms.
• Inform your doctor in case you or your partner is pregnant, a lactating mother or plan to conceive a child as this drug could harm the developing fetus.
• Breast feeding is not recommended while undergoing this treatment as it could enter the breast milk and harm the baby.

Capecitabine chemotherapy is combined with conventional chemotherapy for better results. It is also used when tumors do not respond to some other drugs like 5-FU or an Anthracycline. Capecitabine is usually given as a single agent. However, new protocols are being worked out wherein this drug is used with drugs like Docetaxel.