5-Fluorouracil (5-FU) is an antimetabolite frequently used in the treatment of cancer. The most common adverse reactions are acute gastrointestinal effects and bone marrow suppression while neurological, ocular and dermatological toxicities are unusual. Several cutaneous manifestations can be found. They are hyperpigmentation, maculo-papular eruption and palmar-plantar erythrodysesthesia (PPES) promptly reversed with discontinuation of 5-FU. The etiopathogenesis of such manifestations is still unknown particularly as regards PPES, but it has been postulated that the local drug accumulation secondary to different scheduling (continuous infusion instead of bolus infusion), the total amount of drug, alcoholism, local trauma, increased blood flow could be responsible for them. In this study we have reported 10 cases of dermatological toxicity (1 of these had PPES) observed from January '91 to December '93 in 81 patients treated with bolus injection of 5-FU containing combination chemotherapy.