This graduation project focused on reducing the environmental impact of syringes on the Intensive Care Unit (ICU) of Erasmus University Medical Centre (MC) by designing solutions based on circular economy. The ICU of Erasmus MC produces an excessive amount of waste and initiated the transition towards a circular ICU. Syringes and their packaging are defined as an impact hotspot product at the ICU, due to the product properties, extensive use (24 per patient per day), and the fact that it is a single-use disposable product. The underlying problem of the high environmental impact of syringes is the current linear life cycle. This needs to be transformed into a more circular system by design, to limit the amount of waste and to reduce the use of natural resources. The goal of this project was therefore to redesign the syringes, their packaging and their use, according to circular design strategies suitable for medical products, to decrease the environmental impact. The use of syringes should remain convenient and safe for the healthcare staff and patients. Research was executed to understand the context. This consisted of literature, user and product research. Furthermore, a waste audit and a life cycle analysis were performed. It showed that decreasing the impact of syringes is not only about the product itself. Manufacturing, preparing, using and disposing of all contribute to the environmental impact of the syringe. Various possible interventions were derived from this research. Firstly, adapting the infection prevention protocol and behaviour of the staff could lead to a decrease in unused disposed syringes. Secondly, separating infectious waste from general hospital waste properly could result in opportunities for recycling. Thirdly, the syringe itself can be redesigned to reduce the impact by changing the material to a sustainable alternative and redesigning the shape for (partial) reuse. Lastly, the impact of the filling process could be reduced. It was concluded from research that prefilled sterilised syringes (PFSS) are more environmentally friendly than manually filled syringes because they are produced in large batches and, therefore, have fewer by-products per syringe. However, a life cycle analysis of the filling process of PFSS showed various impact hotspots in this filling process, such as the sterilisation phase, materials used, and left-over medication. The final design is a process optimisation for batch-produced PFSS, based on circular strategies such as reduce, reuse, rethink and repurpose. Interventions include: eliminating the first sterilisation phase, reduce left-over medication and change from steam to gamma sterilisation. The proposed interventions have been evaluated by discussion. In the end, the environmental impact of syringes is reduced by optimising the filling process, which resulted in decreasing the amount of waste, material, energy and water usage, while remaining safe and without increasing the workload of the staff of the ICU.