A system and method for processing keystrokes made while operating a medical device to prevent keypad entry errors. The key press-to-press time is monitored and a subsequent key press rejected if the actual key press-to-press time is shorter than a key press-to-press limit. The actual key inactive time between the release of a key and the subsequent press of a key is compared to an inactive time limit. The subsequent key press is rejected if the actual inactive time is shorter than the inactive time limit. Alerts are provided and further key presses are ignored until the operator presses a CLEAR key. The active time of a key press is monitored and compared to an active time limit. If the actual key press active time exceeds the key press active time limit, an alert is provided but the key press is recognized. An adaptive approach is disclosed in which key presses of an operator are monitored and timing limits modified in accordance with the keying patterns of that operator.