Systems and methods are provided for detecting changes or fluctuations in an analyte concentration signal that are abnormal, e.g., exceed a predetermined threshold, current trend of analyte concentration measurements, etc. Signals indicative of an analyte concentration in a host may be received from an analyte sensor. The signals may be monitored, and a determination can be made as to whether there is a change in the signal. Upon detecting such a change, the change can be compensated for such that a representation of the signal indicates the analyte concentration. Optionally, the cause of the detected changes or fluctuations can also be determined and information regarding the detected changes or fluctuations can be recorded and analyzed for subsequent optimization of the systems and methods as well for transmitting alerts, notifications, etc. to a user to take corrective action.