Capecitabine is an oral chemotherapy drug used to treat several types of cancer, including colorectal, breast, gastric, esophageal, and pancreatic cancers. Sold under the brand name Xeloda, it belongs to a class of drugs called nucleoside metabolic inhibitors. Unlike many chemotherapy treatments that require IV infusion at a clinic, capecitabine is taken as a tablet at home.
Cancers Treated With Capecitabine
Capecitabine has FDA-approved uses across five cancer types, sometimes as a standalone treatment and sometimes combined with other therapies.
Colorectal cancer is the most common reason capecitabine is prescribed. It’s approved for three distinct scenarios: as a follow-up treatment after surgery in patients with Stage III colon cancer, as part of chemoradiation for locally advanced rectal cancer before or after surgery, and as a treatment for metastatic or inoperable colorectal cancer. In each case, it can be used alone or alongside other chemotherapy drugs.
Breast cancer treatment with capecitabine applies to advanced or metastatic disease. It can be used on its own when certain other chemotherapy classes aren’t appropriate, or in combination with another drug after the cancer has progressed on a prior treatment regimen.
Gastric, esophageal, and gastroesophageal junction cancers are treated with capecitabine as part of a combination regimen. This includes patients with inoperable or metastatic disease, as well as a specific use for HER2-positive metastatic gastric or gastroesophageal junction cancer in patients who haven’t received prior treatment for metastatic disease.
Pancreatic cancer is the newest approved indication. Capecitabine is used after surgery for pancreatic adenocarcinoma as part of a combination chemotherapy plan.
How Capecitabine Works
Capecitabine is a prodrug, meaning it’s inactive when you swallow it. Once absorbed, your body converts it through three enzymatic steps into 5-fluorouracil (5-FU), which is the compound that actually fights cancer. The key advantage of this design is that the final conversion happens preferentially inside tumor tissue, concentrating the active drug where it’s needed most. 5-FU interferes with DNA and RNA production in rapidly dividing cells, slowing or stopping tumor growth.
This targeted activation is what makes capecitabine an oral alternative to intravenous 5-FU, which has been a cornerstone of cancer treatment for decades. For many patients, taking pills at home is far more convenient than repeated clinic visits for IV infusions.
How It’s Taken
Capecitabine tablets are swallowed whole with water within 30 minutes after a meal. Food actually slows the drug’s absorption and reduces peak levels in the blood, which is part of why the with-food instruction matters. In clinical trials, all patients were directed to follow this timing.
Treatment typically follows a cyclical schedule. You take the medication for a set number of days, then have a rest period before the next cycle begins. The exact schedule and whether capecitabine is combined with other treatments depends on the cancer type and your oncologist’s plan.
DPD Deficiency Testing Before Treatment
Before starting capecitabine, the FDA recommends genetic testing for a condition called DPD deficiency. DPD is the enzyme your body uses to break down 5-FU after it’s done its job. People who lack this enzyme, either partially or completely, can’t clear the drug normally, leading to dangerous buildups that cause severe or even fatal side effects.
The FDA’s labeling now carries a boxed warning (the most serious type) highlighting this risk. Patients with complete DPD deficiency should not receive capecitabine. Those with partial deficiency may still be candidates, but their dosing needs to be individually adjusted. Testing should happen before the first dose unless treatment is urgently needed.
Common Side Effects
Hand-foot syndrome is one of the most characteristic side effects of capecitabine. It causes redness, swelling, tingling, and sometimes painful blistering on the palms of the hands and soles of the feet. In a study of 446 patients, about one in three (32.7%) developed hand-foot syndrome, and roughly 17% experienced it at a moderate or severe level. If symptoms become significant, your oncologist will typically reduce the dose or pause treatment until they improve.
Other common side effects include diarrhea, nausea, vomiting, fatigue, and mouth sores. These overlap with side effects seen in other chemotherapy regimens, though many patients find capecitabine more manageable than IV alternatives. Blood counts are monitored throughout treatment because capecitabine can lower white blood cells, red blood cells, and platelets.
Important Drug Interactions
Capecitabine has a notable interaction with blood thinners in the warfarin family. It inhibits a liver enzyme involved in processing these medications, which can cause their blood-thinning effect to become dangerously strong. Patients on warfarin or similar anticoagulants need frequent monitoring of their clotting levels throughout treatment and for a period after stopping capecitabine, with dose adjustments as needed.
Your oncology team will review all your medications before starting treatment, as capecitabine can interact with other drugs as well. This includes certain anti-seizure medications and other compounds processed through similar liver pathways.