A non-electric, mechanically-powered (e.g., a spring mechanism) device designed for the continuous or intermittent infusion of medication, typically for antibiotic therapy, chemotherapy, or pain management by intravenous (IV), subcutaneous, intramuscular, or epidural routes. It is primarily designed to be worn by the patient during ambulation in the home. It may be used for patient-controlled analgesia (PCA), and may include mechanical indicators for flow and fluid level status. This is a reusable device.