A portable, battery-driven, programmable drug infusion system which administers up to four different drugs through a single i.v. line is described ("IntelliJect I.V. Drug Delivery System"). The IntelliJect System can be used for a wide range of simple and complex regimens, including cytostatic therapy, antibiotic therapy, antiemetic therapy or pain control. If the actual drugs are not compatible, one channel can be programmed for flushing with sodium chloride. The system assures infusion of the right drug at the right time, while allowing delivery of preferred regimens in all settings--hospital, outpatient and home. A central venous access is necessary when used in an outpatient setting. The system needs minimal nurse or patient manipulation. Chemical stability and questions concerning microbiological contamination must be clarified, because drugs will be in the pump from several hours to several days. Applications of the system for cancer treatment are described, and documentation of patient preference of such a system is demonstrated. "IntelliJect I.V. Drug Delivery System" has the potential of optimizing cancer therapy, with regard to both quality of life and scheduling of cytotoxic drugs which can reduce toxicity and thereby possibly allow dose escalation.