The most common side effects of Xeloda 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. Many people may become anemic during treatment, meaning that their red blood cell count decreases.

Other side effects include 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 may occur as well.

Some side effects are manageable, but contact your doctor immediately if you experience four or more bowel movements than usual, vomiting more than once in a 24 hour period, if nausea is so extreme that you’re eating much less, have stomatitis, have Hand-and-Foot syndrome, or have a fever greater than 100.5 degrees Fahrenheit.

These side effects may differ when taking Xeloda with docetaxel (Taxotere).