Background/aim: Capecitabine is a prodrug of 5-fluorouracil and has shown significant antitumor activity. The main adverse effects are hand-foot syndrome, diarrhea, and dermatitis. In recent years, hypertriglyceridemia has been reported in patients treated with capecitabine. Dyslipidemia is a rare but important side effect of capecitabine. The aim of this study is to examine the changes in lipid levels during capecitabine treatment and to raise awareness of pharmacovigilance.