Needle devices are described. The needle devices can have a catheter hub, a needle hub, and a valve system for controlling fluid flow through the catheter hub. The valve system can include a valve and a valve retainer. The valve can have flow holes for fluid flow therethrough or can have a valve piece for controlling flow through flow holes located externally of the valve. A needle guard is usable with the needle device to block a tip of the needle. A valve opener can also be used to open the valve.