A catheter insertion device that allows for single-handed insertion of the catheter within the vasculature of the patient is disclosed. The catheter insertion device includes a handle, a needle cannula partially within the handle, a guidewire partially within the handle and the needle cannula, and a first actuator connected to the handle and the guidewire. The first actuator is movable in a proximal direction relative to the handle to cause the guidewire to move in a distal direction away from the handle, and is movable in a distal direction relative to the handle to cause the guidewire to move in a proximal direction towards the handle. The catheter insertion device can also include a needle support that stabilizes the needle cannula during insertion of the needle cannula into a patient.