The most common side effects with Glivec (seen in more than 1 in 10 patients) are neutropenia (low white blood cell counts), thrombocytopenia (low platelet counts), anaemia (low red blood cell counts), headache, nausea (feeling sick), vomiting, diarrhoea, dyspepsia (indigestion), abdominal (tummy) pain, oedema (fluid retention), rash, muscle spasm and cramps, muscle and joint pain, and fatigue (tiredness).